Jason Bay, center, leaves the game in the second inning....

Jason Bay, center, leaves the game in the second inning. (June 15, 2012) Credit: Jim McIsaac

The day after sliding headfirst into the leftfield wall while trying to make a diving catch, Jason Bay was placed by the Mets on the seven-day concussion disabled list Saturday.

Mets manager Terry Collins said he wouldn't be surprised if Bay is sidelined longer than that. This is Bay's second concussion in less than two years -- he missed the final two months of the 2010 season after crashing into a wall in Los Angeles -- and that gives Collins some cause for concern.

"I'm very worried because Jason's first one was pretty severe and he hit that wall [Friday] pretty hard," Collins said. "He's pretty sore today, real sore. We're just going to have to bide our time and see how he comes out here the next few days. I don't know how long it's going to be, but my guess is that it will take a little bit of time for him to get back."

The Mets activated Justin Turner from the disabled list to take Bay's roster spot. Turner has been out since spraining his right ankle May 28. Scott Hairston replaced Bay in the starting lineup Saturday night against the Cincinnati Reds.

Bay injured himself in the second inning Friday night when he fell trying to field Jay Bruce's second-inning hit. Bay struggled to his feet and threw the ball back in, but Bruce ended up with an inside-the-park home run.

Bay, 33, has had a difficult time since leaving the Red Sox for the Mets and a four-year, $66-million contract. Expected to provide power, he has suffered a string of injuries and hit only 22 home runs in 240 games during 2½ seasons with the Mets.

After hitting his head, Bay wanted to stay on the field, Collins told reporters, but the manager nixed that idea. As Collins and trainer Ray Ramirez escorted him off the field, Bay was booed by a portion of fans. The scene was upsetting for Mets reliever Jon Rauch, who scolded the boobirds on Twitter.

"Very disappointed with the fans who booed Jason Bay as he came off the field," Rauch wrote. "This is a serious injury that affects his livelihood and his well-being. He plays his heart out every time he takes the field. It's very unfortunate that he's had to deal with multiple concussions and other injuries -- we all have him and his family in our thoughts and prayers for a speedy recovery."

No one has spoken with Bay since Friday; Collins said doctors wanted him to spend time quietly resting at home. Josh Thole, who has suffered multiple concussions in his career, spent 10 days in his bed, not moving, after suffering his latest concussion last month. He said the worst thing about getting through the injury is that it seems as if your head is never going to stop hurting.

"For however long they persist or however long they go on, that's the hardest part for the headaches. They just don't go away," he said. "It's tough."

Thole said Bay has to take his time before returning, but he doesn't think the concussion will change the way Bay plays his position when he returns.

Said Thole: "Nothing you can do about it. You just go back to playing the game hard. If it happens, it happens. If not, great."

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