ST. LOUIS -- Every time the phone rang in the Padres bullpen Friday, a rush of adrenaline would overcome an eager Sean O'Sullivan. Some relievers would immediately react to the call, instinctively knowing it's time to warm up before their names are even mentioned.
But not O'Sullivan. This was a relatively foreign situation for the 25-year-old right-hander who was recently relegated to the 'pen, just six days after his first and only start of the season. He hadn't made a relief appearance since April 6, 2011 with the Kansas City Royals. Of his 45 career games, just 10 have been as a reliever.
"My whole career, I've basically been used to having 35, 40 minutes to get ready for a game, so my body is kind of trained that way," O'Sullivan said. "It's a whole lot different to say, 'Hey, get up, get hot, we're gonna need you in two batters, or three batters or one batter. That's going to be an adjustment."
O'Sullivan was called upon to pitch the seventh and the eighth innings on Friday against the Cardinals. He surrendered three runs on five hits and one walk in a game that was decided by three scores.
"[Friday], I didn't feel very prepared for the situation," O'Sullivan said. "But I won't let that happen again."
Manager Bud Black said the idea behind the move is to give the Padres an extra long reliever, offering another option to soak up some innings if a starter were to get into some early trouble.
O'Sullivan still considers himself a starter, believing that's likely where his career longevity lies and where he's been most successful. But he said he's open to helping the team in whatever way he can, and he understands he can improve as a pitcher, no matter when he enters the game.
"Any time you're on the mound in the big leagues throwing pitches to hitters, you're finding something out about yourself," O'Sullivan said. "If they're good things, you take those and you lock them in your safe and you have them ready for next time. If they're bad things, you find something to improve on."
Chad Thornburg is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.