PORT ST. LUCIE, Fla. - The entire Mets pitching staff stood behind Matt Harvey Friday, forming a blue wall of solidarity as the big moment finally arrived.

It had been 18 1/2 months since he had worked in a bullpen warming for a start. Now everybody got to see if anything had changed.

Harvey did not disappoint.

In his first game action since undergoing Tommy John surgery, the Mets' ace hit 99 mph on the radar gun and pitched two perfect innings in a 5-4 walk-off win over the Tigers.

"I'm just excited," Harvey said afterward. "I'm not trying to deny that I'm not excited to be back. But for me, I know there's a long way to go."

It was vintage Harvey. With a straight face, he paid lip service to the idea of taking his time. But on the mound, he pitched with the intensity of a playoff game.

The final tally: 25 pitches thrown, six batters faced, three strikeouts, two broken bats, no hits, no walks, no problems. And, of course, thousands of fingers that were uncrossed.

"Like I said," he said, "I feel like I never left."

From the electricity on the mound to the buzz in the stands, it was as if Harvey picked up where he left off on Aug. 24, 2013, his final start (also against the Tigers) before doctors discovered the torn ligament that led to surgery two months later.

Tradition Field hosted a sellout of 7,444, with only standing-room tickets available as the first pitch neared.

Those who scored seats whispered among themselves about those who had paid as much as $150 for the privilege.

"I felt the buzz right when I pulled up in the parking lot," Travis d'Arnaud said. "It was the first spring training game I've been nervous for in a while."

When asked why, he shrugged: "Harvey Day."

Harvey, 25, certainly wasn't immune to the excitement. Before his start, he was instructed by manager Terry Collins not to throw the ball during pitchers' fielding practice. Harvey made throws anyway. And the adrenaline only spiked as game time neared.

"I could hear the fans cheering when I ran out," said Harvey, who will make his next start Wednesday. "That was really special. That moment really reminded me of the All-Star Game and the support I was given there. That was really special. That was something that I'll remember for a long time."

Harvey typically throws 35 pitches in the bullpen before a game. On Friday, pitching coach Dan Warthen said the number was closer to 50.

Said Warthen: "I think goose bumps got all over almost everybody out there."

Harvey didn't take long to show that to him, the Grapefruit League would be no different from the National League.

His first pitch to Tigers leadoff man Anthony Gose: a 98-mph fastball. His last: a nasty 3-and-2 curveball that froze Bryan Holaday after a pair of 99-mph heaters. Harvey's fastball, Warthen said, already was in "midseason form."

"It's just like he left off," David Wright said. "That's the biggest compliment you can give him. It reminded me of the last time I saw him on the mound."

Harvey found his manager in the dugout and joked about pitching a few more innings.

For now, even Collins had to laugh. He didn't expect anything less.

"Yeah," said Collins, who has the unenviable job of keeping Harvey from pushing too much. "It won't be as funny in June."