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SAN DIEGO -- Terry Collins is like just about everyone else when it comes to rookie starter Chris Flexen.

The manager is not quite sure what the New York Mets have with the talented right-hander who will make his major-league debut Thursday against the San Diego Padres.

"I do know he can hit a golf ball a long way," Collins said.

Collins and Flexen's paths crossed at spring training, when both were aiming for the backside of the driving range net. Flexen came over and introduced himself, and that sparked a curiosity in Collins about seeing him pitch that spring.

"The movement on his fastball and how he keeps the ball down was what I had heard about," Collins said. "So I was anxious to see him pitch."

Instead, Flexen tweaked his knee, and Collins was unable to watch him pitch. That all will change when Flexen, a 14th-round pick in 2012, toes the rubber at the Padres' downtown digs Thursday.

"There is some nice talk about him," Collins said.

That chatter doesn't entail Flexen's golf game. Instead it's how he's blasted through the Class A and Double-A ranks, pitching to a 6-1 mark with a 1.66 ERA.

But just as it's a long way from the driving range to the first tee, it's an equally daunting leap from Double-A to the majors. Flexen is the first Mets starter to skip Triple-A since Mike Pelfrey in 2006.

"He's very, very excited and all fired up," Collins said. "And I told him what I tell them all: Do what got you here and that will keep you here.

"Especially a pitcher in his first start; just pitch your game."

Still, that's a big jump for a pitcher three years removed from Tommy John surgery.

"The Eastern League is a tough league, to me," Collins said about Flexen's last stop in Binghamton. "But it's all about if he doesn't try to change anything when he gets here. If he throws the ball with movement and keeps the ball down, he'll get outs."

The Padres are going to counter with Luis Perdomo (4-5, 4.71) as he faces the Mets for the first time. But Perdomo, whose 10 quality starts are second on the team, has shown well against NL East teams, winning four of five decisions with a 3.76 ERA.

The Padres' righty had been on a roll before his last start, winning three straight outings. But on Friday against the San Francisco Giants, he gave up four runs and eight hits in six innings. In the previous start, he was ambushed to the tune of seven runs and six hits in just 2 1/3 frames.

The Mets and Flexen might have to keep an eye on Perdomo at the plate. He notched his third triple of the year against the Giants. He's the first pitcher with three triples since Dontrelle Willis did it 10 years ago.

"He's a crazy athlete," Padres manager Andy Green said. "He can fly. I'd venture to say there's probably not a pitcher in the game that runs much better than he does."