History of Kenley Jansen in Timeline

Kenley Jansen is a professional baseball pitcher from Curaçao, currently playing for the Los Angeles Angels in MLB. He previously played for the Los Angeles Dodgers, Atlanta Braves, and Boston Red Sox. He is known for his cutter, which he developed into one of the most dominant pitches in baseball. Jansen has been a multiple-time All-Star and holds the Dodgers' franchise record for career saves. He is one of the prominent closers in recent MLB history.

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Full Timeline Career & Achievements Success & Recognition

September 30, 1987: Kenley Jansen's Birth

On September 30, 1987, Kenley Geronimo Jansen was born. He is a Curaçaoan professional baseball pitcher currently playing for the Los Angeles Angels of Major League Baseball (MLB).

Others born on this day/year

1991: Broke Team Records

In 2015, Kenley Jansen broke Jay Howell's team records, set in 1991, of 13 games without a walk to start a season and 20 strikeouts without a walk to start a season.

November 17, 2004: Signed by Dodgers Organization

On November 17, 2004, Kenley Jansen was signed as an undrafted free agent catcher by the Dodgers organization and was assigned to the Rookie Class Gulf Coast Dodgers.

2004: Signed by the Dodgers

In 2004, Kenley Jansen was signed as an undrafted free agent by the Los Angeles Dodgers.

2007: Split Season Between Raptors and Loons

In 2007, Kenley Jansen split his season between the Ogden Raptors and the Class-A Great Lakes Loons of the Midwest League, hitting .207 in 73 games.

2008: Played with Great Lakes Loons

In 2008, Kenley Jansen played with the Great Lakes Loons, hitting .227 with 9 home runs in 79 games. He was also selected to the mid-season Midwest League All-Star game.

November 19, 2009: Added to Dodgers 40-Man Roster

On November 19, 2009, Kenley Jansen was added to the Los Angeles Dodgers 40-man roster.

2009: World Baseball Classic 2009

In 2009, Kenley Jansen played as the starting catcher for the Netherlands in the World Baseball Classic. During the Netherlands' upset victory over the Dominican Republic, Jansen threw out Willy Taveras attempting to steal third base in the ninth inning, which was a key play.

2009: World Baseball Classic and Minor League Season

In 2009, Kenley Jansen was the starting catcher for the Netherlands team in the World Baseball Classic, where he played a key role in an upset win against the Dominican Republic. He also played for the Inland Empire 66ers and the Triple-A Albuquerque Isotopes during the 2009 season.

2009: Experimenting with Changeup in 2009

In the 2009 season, Kenley Jansen experimented with a changeup.

2009: Position Change to Pitcher

In the second half of the 2009 season, the Dodgers organization convinced Kenley Jansen to switch from catcher to pitcher due to his offensive struggles. He began working with Charlie Hough to make the conversion, pitching for the Inland Empire 66ers and later in the Arizona Fall League for the Peoria Javelinas.

May 15, 2010: Promoted to Double-A Chattanooga

On May 15, 2010, Kenley Jansen was promoted to the Double-A Chattanooga Lookouts, where he was selected for the mid-season Southern League All-Star Game.

July 23, 2010: Promotion to the Dodgers

On July 23, 2010, Kenley Jansen was promoted to the Los Angeles Dodgers.

2010: First Major League Season

In 2010, Kenley Jansen appeared in 25 games for the Dodgers, recording a 1–0 record, a 0.67 ERA, and four saves.

2010: MLB Debut

In 2010, Kenley Jansen made his Major League Baseball debut for the Los Angeles Dodgers after converting from a catcher to a relief pitcher in the minor leagues.

2011: Key Member of Bullpen

In 2011, Kenley Jansen became a key member of the Dodgers' bullpen, achieving a 2–1 record with a 2.85 ERA and five saves. He also set a new Major League season record with 16+1⁄3 strikeouts per nine innings.

2011: Irregular Heartbeat Diagnosis

In 2011, Kenley Jansen was diagnosed with an irregular heartbeat (atrial fibrillation) and missed time while on blood thinners to prevent clots.

2011: Experimenting with Changeup in 2011

In the 2011 season, Kenley Jansen experimented with a changeup.

May 2012: Named Dodgers' Closer

In May 2012, Kenley Jansen took over as the Dodgers' closer after Javy Guerra struggled in the role. Jansen was later replaced as closer by Brandon League due to heart problems. He finished the season with a 5–3 record, 2.35 ERA, 99 strikeouts, and 25 saves.

October 24, 2012: Heart Ablation Procedure

On October 24, 2012, Kenley Jansen underwent a 3-hour catheter ablation procedure to address a recurrence of an irregular heartbeat. During the procedure, Koonwalee Nademanee identified and cauterized abnormal tissue in his left atrium to prevent abnormal electrical signals.

2012: Dodgers' Closer

In 2012, Kenley Jansen became the Los Angeles Dodgers' closer.

2012: Pitch Usage and New Fastball in 2012

In 2012, Kenley Jansen primarily relied on his cut fastball, using it about 93% of the time. He also debuted a four-seam fastball at the end of the 2012 season.

2012: Mention of Previous Heart Procedure

In November 2018, during another heart ablation procedure, doctors discovered that small veins near the site of Kenley Jansen's 2012 procedure had grown and were agitated by dehydration, which caused the irregular signals that occurred in Denver.

2012: High Strikeout Rate in 2012

Through the 2012 season, Kenley Jansen achieved an extremely high strikeout rate of 14.6 strikeouts per 9 innings pitched, ranking as the second-highest in history among pitchers with at least 140 innings.

March 16, 2013: Birth of Daughter

On March 16, 2013, Kenley Jansen's daughter, Natalia Hannah Jansen, was born.

2013: Resumed Closer Role

In 2013, Kenley Jansen began the season as the setup man but resumed the role of closer when Brandon League struggled. He finished the season with a 4–3 record, a 1.88 ERA, and 28 saves.

2013: World Baseball Classic 2013

In 2013, Kenley Jansen was a late addition to the Netherlands national baseball team for the World Baseball Classic. Having transitioned to pitching in late 2009, he joined the roster for the semi-finals but did not play in the game.

2013: Most Strikeouts

In 2017, Jansen recorded his 36th strikeout of the season, setting an MLB season record for most strikeouts without giving up a walk. The previous record was held by Cardinals starting pitcher Adam Wainwright, who struck out 35 batters before giving up a walk in the 2013 season.

February 11, 2014: Contract with the Dodgers

On February 11, 2014, Kenley Jansen avoided his first arbitration hearing by signing a $4.3 million contract with the Dodgers.

2014: Pitching Style in 2014

In 2014, Kenley Jansen's cut fastball exceeded 100 mph.

January 16, 2015: Avoided Arbitration

On January 16, 2015, Kenley Jansen avoided arbitration by signing a one-year $7.425 million contract with the Dodgers.

August 16, 2015: Birth of Son

On August 16, 2015, Kenley Jansen's son, Kaden Isaiah Jansen, was born.

January 15, 2016: Signed a Contract with the Dodgers

On January 15, 2016, Kenley Jansen signed a one-year, $10.65 million contract with the Dodgers in his final year of arbitration.

2016: NL Reliever of the Year

In 2016, Kenley Jansen was named the National League Reliever of the Year.

January 10, 2017: Re-signing with the Dodgers

On January 10, 2017, the Dodgers announced that they had re-signed Kenley Jansen to a five-year, $80 million contract.

2017: Slow Start Due to Workload

Due to the workload in 2017, Jansen was slow-played during spring training and had two blown saves during a shaky April.

2017: Second NL Reliever of the Year Award

In 2017, Kenley Jansen earned his second consecutive National League Reliever of the Year Award.

2017: NL Saves Leader

In 2017, Kenley Jansen led the National League (NL) in saves.

2017: World Baseball Classic 2017

In 2017, after initially declining due to his recent contract, Kenley Jansen joined Team Netherlands for the World Baseball Classic semi-finals. He pitched a scoreless 9th inning against Team Puerto Rico, striking out two, but the team lost in the 11th inning.

2017: 2017 World Series Performance

In the 2017 World Series against the Houston Astros, Kenley Jansen allowed two runs, including a solo homer. It was his first blown save in the postseason, ending his MLB record of converting his first 12 post-season save opportunities. He also picked up the loss in Game Five of the series. Overall, he pitched 8+2⁄3 innings over six games, with two saves and three runs allowed as the Dodgers lost the series in seven games.

June 2018: Prior Extended Save

Kenley Jansen's five-out save in a series against the Mets was his first since June 2018 in Pittsburgh.

August 9, 2018: Heart Condition Recurrence in 2018

On August 9, 2018, Kenley Jansen experienced a recurrence of his irregular heartbeat before a game in Denver. He was placed on the 10-day disabled list, and while medication controlled the condition, it initially led to fatigue and blown saves. He stayed in Los Angeles when the team returned to Denver in September due to stroke risk at high elevation, and he completed the season providing scoreless relief in the postseason.

August 22, 2018: Birth of Son

On August 22, 2018, Kenley Jansen's son, Kyrian Jeremiah Jansen, was born.

November 26, 2018: Heart Ablation Procedure in 2018

On November 26, 2018, Kenley Jansen underwent a 5+1⁄2-hour heart ablation procedure in Los Angeles. The doctor found that small veins near the site of his 2012 procedure had grown and were agitated by dehydration. Following recovery, Jansen adopted a healthier diet and lost 25 pounds, no longer needing blood-thinning medication.

2018: Struggles in the 2018 World Series

During the 2018 World Series, Kenley Jansen struggled, blowing two save opportunities by allowing game-tying home runs to Jackie Bradley Jr. and Steve Pearce, as the Dodgers lost the series to the Boston Red Sox in five games.

2018: Third Straight All-Star Game Selection

In 2018, Kenley Jansen was chosen for his third straight all-star game after turning around his performance in May, June, and July.

April 7, 2019: Four-Out Save

On April 7, 2019, Kenley Jansen recorded a four-out save against the Colorado Rockies at Coors Field in Denver.

June 15, 2019: Debuted Intentional Balk

On June 15, 2019, Kenley Jansen debuted the intentional balk in a game against the Chicago Cubs. This strategy, developed with bench coach Bob Geren, involves balking a runner from second to third base with two outs to prevent sign stealing.

2019: Dominant Performance in NLDS

During the 2019 NLDS, Kenley Jansen faced five batters and did not allow any of them to reach base.

2019: 300 Career Saves

In 2019, Kenley Jansen became the 30th pitcher to reach 300 career saves.

July 12, 2020: Reports to Summer Camp After COVID-19 Recovery

On July 12, 2020, Kenley Jansen reported to summer training camp for the first time after recovering from COVID-19.

2020: 2020 Season Performance

In 2020, Kenley Jansen's season was impacted by a COVID-19 infection, affecting his conditioning. Despite this, he pitched 24.1 innings over 27 games, achieving a 3–1 record with a 3.33 ERA and 11 saves, ranking third in the National League. He also led the league with 24 games finished. In the postseason, he had mixed results, including blowing a save in Game 4 of the 2020 World Series against the Tampa Bay Rays, setting a new World Series record.

September 12, 2021: Birth of Daughter

On September 12, 2021, Kenley Jansen's daughter, Key’Gia Keziah Jansen, was born.

2021: 2021 Season and Postseason Performance

In 2021, Kenley Jansen achieved his 1,000th strikeout, finishing the season with 38 saves, a 2.22 ERA, and 86 strikeouts in 69 innings. During the postseason, in the National League Wild Card Game against the St. Louis Cardinals, he secured a win with a scoreless ninth inning, and he also pitched in five of the six games in the 2021 NLCS against the Atlanta Braves, recording a save in Game 3.

March 18, 2022: Signs with the Atlanta Braves

On March 18, 2022, Kenley Jansen signed a one-year contract worth $16 million with the Atlanta Braves.

June 2022: Irregular Heartbeat Recurrence in 2022

In June 2022, Kenley Jansen again dealt with an irregular heartbeat.

December 13, 2022: Signs with the Boston Red Sox

On December 13, 2022, Kenley Jansen signed a two-year contract with the Boston Red Sox.

2022: Signed with Braves

In 2022, after 11 years with the Dodgers, Kenley Jansen entered free agency and signed a one-year deal with the Atlanta Braves. He later signed with the Red Sox.

May 10, 2023: Reaches 400 Saves

On May 10, 2023, Kenley Jansen became the seventh pitcher in MLB history to record 400 saves.

2023: 400 Career Saves

In 2023, Kenley Jansen became the 7th pitcher to total 400 career saves.

2023: World Baseball Classic 2023

In 2023, Kenley Jansen represented the Netherlands national baseball team at the World Baseball Classic.

2024: 2024 Season Performance

In 2024, Kenley Jansen began the season as Boston's closer and earned his 425th career save on April 20, passing John Franco for fifth place on the all-time list. Jansen finished the 2024 season with 27 saves, a 3.29 ERA, and 62 strikeouts in 54+2⁄3 innings.