Hernandez and Tillman both made their major league debuts last year with Baltimore. They were competing this spring to fill out the rotation behind Kevin Millwood, Jeremy Guthrie, Brad Bergesen and Brian Matusz.
The winner was Hernandez, mainly because he showed more control than his counterpart in a duel of young right-handers.
Hernandez is 1-1 with a 3.00 ERA, three walks and 20 strikeouts. Tillman is 0-3 with a 3.86 ERA and has given up three homers and nine walks in 16 1/3 innings.
"I knew it was going to be a competition going into spring training," Hernandez said. "I wanted to have fun, be more relaxed than I was last year and it paid off. I was able to do well enough in the eyes of the coaches."
The result did not come as a surprise to Tillman, who said, "I could kind of see it coming the last couple of weeks."
Hernandez went 4-10 with a 5.42 ERA last season. Tillman was 2-5 with a 5.40 ERA.
Tillman contended his poor performance could be attributed in part to his desire to incorporate a cut fastball into his repertoire.
"If I were to have stayed with my fastball, changeup, curveball, I think it would have been a totally different outcome," he said. "I was working on the cutter. I'm not saying where I would have been, but the results would have been different. But I'm excited, I think the cutter is going to help me."
Tillman is expected to begin the season with Triple-A Norfolk.
"I think consistency's the thing, throwing all my pitches for strikes," he said. "I want to focus on that cutter now; it's a new pitch and I want to see how that comes along. They were happy with the progression that the changeup had last year and they want to see that with the cutter, I think."
Hernandez probably clinched a berth on the team with his performance Saturday against Boston, when he allowed four hits in five scoreless innings and struck out six in a 6-1 victory.