Jansen earned his first Major League win in Saturday's 6-3 win at Houston, lowering his ERA to 0.96.
"I just have fun with the game," said Jansen (1-0). "That's how I've been doing [it]. Just come every day and have fun, and be aggressive.
In 18 games this season, Jansen has 29 strikeouts in 18 2/3 innings. Opponents are batting only .143 (9-for-63).
"Even though they know the fastball is coming, there's late life on it," said Dodgers manager Joe Torre. "Even though they may not be overpowering at times, they're the toughest ones to read. It doesn't matter, lefty, righty, he gets a lot of swings and misses."
Torre can see the 6-foot-5, 257-pound Jansen in a closer's role some day. Jansen still has to build his arm strength up.
"He was protected this year," said Torre. "I think he only repeated one time in back-to-back games. It will be a process. He certainly has the size, and he seems to bounce back."
Jansen sees his future as a closer too.
"I want to be a pitcher like [the Yankees'] Mariano Rivera," said Jansen. "That's my goal, to be like that one day."