Matz’s newest elbow trouble is

BIG Sexy got a big ovation Wednesday night.

Bartolo Colon returned to Citi Field and made his mark, keeping the Mets hitters off-balance while the fans gave him a warm welcome.

As Colon came up to bat in the top of the third, fans rose to their feet and gave him a loud standing ovation as he stepped into the batter’s box.

“To be honest, I didn’t really expect it today,” Colon said. “I was not as surprised on Opening Day but I want to express my gratitude to the Mets fans and how appreciative I am of them for their warm reception again.”

Of course, Colon gave the crowd a chuckle by whiffing on the first pitch he saw.

The Mets, however, were not laughing as Colon silenced their bats by throwing six innings, allowing just two hits and one run while striking out six.

The lone run came on a fifth inning home run from Jay Bruce.

“He is what he is,” Mets manager Terry Collins said after the game. “We’ve sat there in the fourth inning and said this is vintage Bartolo.… He knows what he is doing. You can’t try to swing at everything. Got to go up there and be real patient.”

Colon spent the last three seasons with the Mets, becoming a fan favorite while going 44-34 with a 3.90 ERA in 98 games (95 starts).

But the Mets decided not to bring the 43-year-old back despite the fact that he can clearly still be effective.

“I don’t think Bartolo wanted to come back, given the pitching depth we had and we continue to have,” Alderson said before the game. “The previous year there was a lot of talk about him being a swing man and so forth. I don’t think that was appealing to Bartolo this year. I am speculating, we never really had a chance to talk to him.”

STEVEN Matz said Monday that he had been diagnosed with a flexor tendon strain. Wednesday, Sandy Alderson said the Mets are not exactly sure what is going on with Matz’s elbow. They are concerned about the lefty, who has made just 28 starts over three seasons because of injuries.

“There are a couple of things: Number one, he’s not pitching, he’s not throwing. Number two, doesn’t seem to be a specific injury, just irritation,” the GM said Wednesday. “I know he’s talked about the flexor tendon and that’s a possibility, there’s just a little bit of uncertainty.

“The nice thing is nobody is talking surgery in his case. Not in the realm of possibility,” Alderson continued. “The good thing is I do expect him back relatively soon. When that is, I couldn’t tell you.”

UP IN ARMS

The joke in spring training was that if the Mets could wrap their pitchers in bubblewrap, they would. They started their young arms off so slowly that they were not even allowed to throw to first base during fielding practice. Now, it’s not so funny. With Matz out for at least a month and Seth Lugo trying to rehab a partially torn ulnar collateral ligament, the Mets’ once deep pitching corps is a little thin. So, break out the bubble wrap. “Any time you lose quality starting pitching, you have concerns,” Terry Collins said. “That’s why we’ve got to be more cautious than ever the first weeks of this season, to make sure we don’t overdo it.”

BOUNCING BACK

Juan Lagares, who began the season on the disabled list with a strained left oblique muscle, is expected back some time in the middle of next week. The outfielder will play in a game on Monday, according to Alderson, and “should be back a few days later.”

Brandon Nimmo, who is on the DL with a pulled right hamstring, is progressing but has a bruised hand, so he was not able to take batting practice on Wednesday.

BRUCE GETTING LOOSE

Jay Bruce only has two hits off Bartolo Colon in his career, but both are home runs. The right fielder connected for a solo shot in the fifth inning Wednesday night for the Mets