From BR Bullpen
Kenley Geronimo Jansen
also listed as Kenley Corrales Jansen
- Bats Both, Throws Right
- Height 6' 6", Weight 220 lb.
 Biographical Information
Kenley Jansen, who was a minor-league position player, converted to pitcher in 2009 and was successful enough that he made his major league debut on July 24, 2010 with the Los Angeles Dodgers. In 2011 he broke the all-time strikeout-per-nine-innings record, finishing with 96 strikeouts in 53.2 innings, for a 16.1 ratio of strikeouts per nine innings (minimum 40 innings).
He is the younger brother of former minor leaguer Ardley Jansen. In his first three minor league seasons, he led the league in a defensive department while his offensive production varied. When his career as a catcher stalled, he became a pitcher.
Kenley Jansen was signed by scouts Camilo Pascual and Rolando Chirino for the Dodgers a couple of months after his 17th birthday. He debuted professionally with the 2005 GCL Dodgers (.304/.339/.441) and Ogden Raptors (2 for 11, BB, 5 K, 2B). He led Gulf Coast League catchers with a 1.000 fielding percentage. In 2006, Jansen hit .248/.362/.308 for the GCL Dodgers. He led GCL backstops in putouts. He only was 4 for 33 with no walks and 8 strikeouts for the North Shore Honu that winter. He batted .240/.346/.311 with 50 strikeouts in 183 AB for Ogden in 2007 and .102/.214/.169 with 16 whiffs in 59 AB for the Great Lakes Loons. His .994 fielding percentage led the Pioneer League's catchers.
He was on the preliminary 42-man roster for the Dutch national team for the 2008 Olympics. Of the five catchers listed, he was the only one who had not played for the national team but also the only one with experience in US minor leagues (Tjerk Smeets and Sidney de Jong had played college baseball in the USA). He did not make the final cut.
In 2008, Jansen hit .227/.298/.397 with 9 home runs and 72 strikeouts in 247 AB for Great Lakes. He threw out 35 of 94 attempted base-thieves. In the 2009 World Baseball Classic, Kenley was 1 for 13 with a walk and six strikeouts while sharing catching duties with de Jong. His lone hit was off Roy Oswalt.
Jansen struggled offensively in 2009 with the Inland Empire 66ers (.202/.268/.303 in 26 G) and Albuquerque Isotopes (5 for 27, BB) while throwing out 38% of attempted base-stealers overall. Moved to the mound, he walked 11 in 11 2/3 IP but struck out 19 for the 66ers, posting a 4.63 ERA and registering no decisions. He was then sent to the Arizona Fall League for further development as a pitcher.
Kenley was added to LA's 40-man roster in November 2009. He was 1-1 with 28 strikeouts in 15 innings for the 2010 66ers then went 4-0 with 8 saves, a 1.67 ERA, 50 strikeouts, 17 walks and only 14 hits in 27 innings for the Chattanooga Lookouts. That earned him a trip to the major leagues, only a year after he became a pitcher.
Jansen pitched a scoreless inning against the New York Mets in his major league debut on July 24, 2010, then earned his first major league save by pitching the 9th inning of a 1-0 Clayton Kershaw victory over the Mets the next day. He recorded two strikeouts in each of his first two major league innings. Kenley enjoyed his first major league at-bat, drawing a walk and scoring a run. Manager Joe Torre observed that Jansen seemed to know what he was doing as a batter and a baserunner, and then recalled that a year ago, Jansen had been a catcher. He finished that first season with a record of 1-0, 0.67 and 4 saves in 25 games, striking out 41 batters in 27 innings.
Kenley spent most of 2011 with the Dodgers, making 51 appearances out of the bullpen with a record of 2-1, 2.85, and 5 saves. His 96 strikeouts in 53 2/3 innings gave him the highest ratio ever for a pitcher throwing 40 or more innings. However, he missed four weeks of the season when he was diagnosed with an irregular heartbeat, and had to take blood thinners to control the condition. He had a recurrence of the condition in spring training in 2012, but not severe enough tom place him on the disabled list. He was anointed as the team's closer in late April, replacing Javy Guerra, and did quite well, saving 25 games in 56 appearances while going 5-3 with a 2.54 ERA. He struck out 86 in 56 2/3 innings, an outstanding ratio even if behind the previous season's record pace, and walked only 19. However, on August 29th, he was again sidelined by his recurring heart condition. He came back to pitch in late September, but Brandon League had assumed closer duties in his absence and finished the year in the role. Jansen ended the season with a record of 5-3, 2.35 in 65 games, with 25 saves and 99 strikeouts in 65 innings. On October 23rd, he underwent surgery to correct the heartbeat problem.
- Netherlands Antilles Baseball Federation bio
- 2007 Dodgers Media Guide
- Hawaii Winter League
- World Baseball Classic