LOS ANGELES -- The Los Angeles Dodgers are expected to be without All-Star closer Kenley Jansen for a key weekend series with the Colorado Rockies after a team cardiologist recommended the right-hander not travel to Denver.
Twice in his career Jansen has experienced an atrial fibrillation episode, more commonly known as an irregular heartbeat, while the Dodgers were in the high altitude of Colorado.
The most recent episode happened Aug. 9 before the start of a four-game series at Coors Field, with Jansen calling 911 when an accelerated heartbeat would not subside. His heart had to be shocked back into rhythm at a Denver hospital. Increased elevation can exacerbate an irregular heartbeat.
Jansen went on the 10-day disabled list with an irregular heartbeat and began taking blood-thinning medication. He struggled upon his return, giving up runs in four consecutive outings while taking a loss and blowing two save opportunities. He stopped taking the medication last week.
Jansen addressed the issue via Twitter on Wednesday.
'@Dodgers fans, as u heard, I won't be making the trip to COL. Dr.'s orders. I want to help my team at any cost, but must listen to Dr. To be honest w/you💙issues are scary. Doing great though. I'll join team after COL, continue pushing toward postseason. #KeepKenleysHeartHealthy— Kenley Jansen (@kenleyjansen74) September 5, 2018
The Dodgers began the day a half-game behind NL West-leading Colorado.
"Whenever we get that decision from the doctor it's sort of a no-brainer, but you have to applaud Kenley for feeling good and wanting to still kind of see it through,'' manager Dave Roberts said. "But we sometimes have to take it out of the player's hands to do what is best for him.''
Jansen underwent a heart procedure in 2012 to aid the issue and said last month that he likely will undergo another procedure this offseason.
Jansen will continue to keep his arm loose in Los Angeles while the Dodgers travel to Denver. He is expected to rejoin the team Monday for the opener of a three-game series at Cincinnati.
Roberts said that Jansen was available to pitch Wednesday in the finale of a three-game series with the New York Mets at Dodger Stadium.
The Dodgers could get a boost for the bullpen on Saturday when right-hander Ross Stripling is expected to come off the disabled list after recovering from a back issue. Roberts said the team will go into the series at Colorado without a designated closer.
The Associated Press contributed to this report.