PHOENIX -- Reliever Dan Jennings appeared in 22 games for the Marlins last season over several brief stints with the club. But even though he experienced plenty of success -- allowing four earned runs in 19 innings (a 1.89 ERA) -- he never really got comfortable in the Majors. He was always looking over his shoulder, afraid if he made any mistakes he'd be sent down again.
So after missing out on an Opening Day roster spot, Jennings began 2013 at Triple-A New Orleans, where he worked on his mental approach. He wanted to make sure that when he got another shot with Miami, he'd be ready.
Now 11 appearances into his second big league season after being called up on May 27, Jennings has been fantastic for the Marlins, surrendering only one run over 11 2/3 innings while striking out 10.
"A lot of it is having confidence in yourself and the people around you having confidence in you," Jennings said. "Because once you know that, you can start to build off it. The coaches are sending you out there for a reason, so you just try to take that and run with it."
While Jennings added that sometimes it's good to feel some pressure, he noticed that when he put too much of it on himself, he wasn't being aggressive enough attacking hitters.
"I found I was being really tentative," he said. "You can't pitch that way, you have to know every single pitch you throw is the right one. A lot of it is mental, it's about going out there and pitching with authority."
Jennings has certainly done that in 2013, as none of the six walks he has issued have resulted in runs.
"He's been good, he's done a nice job every time we've put him in there," Marlins manager Mike Redmond said. "He's throwing strikes, and in the big leagues, that's what you need in your relievers."
So where is Jennings' confidence level now compared to last season?
"I'm feeling like I did in Triple-A last year," he said. "Basically I'm pitching care free. I know this is where I'm supposed to be. I'm not tip-toeing around anymore."
Tyler Emerick is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.