SEATTLE -- Ryan Rowland-Smith had already started two games this season before Saturday night's contest against the Rays, but this one was different.

After going down to Triple-A Tacoma for three starts to stretch his arm out and become part of the Seattle rotation, Rowland-Smith went to the mound not as a fill-in like his previous two outings, but as a scheduled starter who has shown that he deserves a shot.

"Yeah, definitely," he said after the game when asked if the feeling was different. "Those starts I had in Triple-A, I got a lot out of that, getting stretched out ... it's a different feel, definitely."

And the Australian lefty looked pretty good on the mound for the most part. He gave up a third-inning solo homer to Gabe Gross but only allowed one run through the first five innings despite throwing more pitches in the fifth inning than he should have thanks to some infield mistakes.

And he stranded all three Rays on base in the fifth with a quality slider to strike out Tampa Bay's Carlos Pena.

"I threw like probably three sliders the whole time I was down in Triple-A the last three starts, so I was throwing that actually a lot tonight. I wasn't expecting to throw it a lot," he said. "It worked well against some of the lefties ... and the curveball felt pretty good. Fastball command was a bit shaky at times. I think that's another thing, too, if you get that fastball, 0-1, over, it makes a huge difference."

Mariners manager Jim Riggleman agreed in his pregame media session on Sunday that Rowland-Smith's fastball needed some work.

"The command of his fastball is now his final thing he's going to have to get. He's got a good breaking ball, and he's got a good presence on the mound. He's competitive. He's got a lot of the attributes you want as a pitcher."

But the start didn't end the way Rowland-Smith wanted it to end. He left the game leading, 5-1, with two outs and the bases loaded in the sixth inning thanks to a walk and another fielding issue. And all three runners would score as the Rays eventually posted a six-spot in that inning.

"I was one pitch away from going six innings with giving up one run," he said. "So that was disappointing, sort of left a bad taste in my mouth coming off."

He also mentioned how he noticed the amount of pitches he threw per batter went down when he got ahead early in the count -- something he will get a chance to work on during his next start on Saturday as he continues to try and prove himself as part of the rotation.