Jonathon Niese delivers a pitch during a spring training workout...

Jonathon Niese delivers a pitch during a spring training workout at Tradition Field in Port St. Lucie, Fla. (Feb. 20, 2013) Credit: Newsday/Alejandra Villa

PORT ST. LUCIE, Fla. -- In Johan Santana, the Mets insist they still see their starter against the Padres on Opening Day.

But in case the lefthander isn't ready, which is a possibility because of Santana's shoulder issues, manager Terry Collins has another alternative.

If Santana can't go, lefthander Jon Niese is the leading candidate to start on April 1.

With Santana still experiencing fatigue in his left shoulder, the Mets have been forced to examine other possibilities to begin the season atop the starting rotation. And although Collins has an intriguing option in 23-year-old righthander Matt Harvey, Collins said Friday that he's leaning toward "more of a veteran guy."

In this case, that veteran is Niese, who threw three scoreless innings in Friday's 6-2 victory over Justin Verlander and the Tigers. Though Niese didn't quite match Verlander's three perfect frames, he was effective, allowing three hits and striking out three in his first appearance against big-leaguers.

"For the most part, all my pitches felt good," said Niese, whose first outing came against the University of Michigan.

Niese, 26, is coming off his most productive season: 13-9 with a 3.40 ERA. Despite battling through fatigue and knee soreness during the homestretch last year, Niese logged a career-best 1901/3 innings. He attributes part of his breakout season to the increased use of his changeup.

"I see the success that Johan has with it," Niese said. "I want to get that pitch as best that I can."

Of course, the Mets wouldn't mind seeing Santana throwing his signature pitch to begin the new season.

"Oh, yeah," Collins said when asked if the Mets are hopeful that Santana will start on Opening Day. "Absolutely."

But Santana's readiness likely will swing on how he looks during the next few days. Collins said he is slated to throw live batting practice Tuesday, which would be his first throwing session off a mound since the team shut him down to build arm strength.

Santana threw in the bullpen twice before the Mets decided he lacked enough arm strength to proceed on a normal throwing schedule. He has been trying to strengthen his shoulder through long-toss sessions, with the distance of his throws increasing over time.

Typically, pitching coach Dan Warthen said he's comfortable with pitchers returning to the mound once they've established they can throw 150 feet with little arc on their throws. Santana, who long-tossed Friday, is nearing that distance. But Warthen said Santana prefers to long-toss from an even longer distance before getting back on a mound.

Even if Santana doesn't start on Opening Day, Collins said it's possible that he simply will be pushed back in the starting rotation, which would allow him a few extra days to prepare for the season.

"If he's not ready for Game 1,'' Collins said, "I think he'll be ready for Game 4."

With David Lennon

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