The Kingdom of the Netherlands will play in the second semifinal game, which will be Monday at 6 p.m. PT. The Dutch will face the Pool 2 winner, which is still being contested at Marlins Park in Miami. The championship game will be Tuesday at 5 p.m. PT. All World Baseball Classic games can be seen on MLB Network and ESPN Deportes.
The 25-year-old Jansen is a native of Curacao in the Netherlands Antilles. The Kingdom of the Netherlands and Japan have reached the semifinals, with their opponents still to be determined.
"He's not missing anything and, actually, we think this will be good for him," said manager Don Mattingly. "He'll get into competition and it will be a good scenario, as far as the competition and energy level, and the fact it will only be a couple of days."
In October, Jansen had surgery to cauterize tissue in an artery that was the cause of his irregular heartbeat, which first surfaced during the 2011 season and again put him on the disabled list last year. That led to the emergence of newly acquired Brandon League as the club's closer.
Jansen, who throws a natural cut fastball similar to Mariano Rivera's, has been working this spring on refining his mechanics.
"I'm trying to be more relaxed with my hands," said Jansen, whose inconsistent mechanics are believed to be responsible for variations in his velocity from the low-90s to the mid-90s.
"When I first came up, I was throwing hard and effortless. Last year it seemed like I was trying to throw hard, and I'm not that guy. I used to be effortless and it just came out hard, and I'm trying to get back to that."
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.