One of the reasons the 38-year-old right-hander decided to pitch this year after his comeback from a third Tommy John surgery in 2010 was to reach that milestone.
At 33 2/3 innings in 2011, Isringhausen is less than 10 frames shy of how many he pitched in his last full season, which came in 2008 with the Cardinals.
"We've reached that time of the year where obviously we'll continue to be careful and monitor things," Mets manager Terry Collins said. "It's no longer, 'Hey look, let's try to get him through the year.' We're at that point."
Collins said that the veteran wants to be put into games and will let his skipper know if anything's up.
"I think in his new role obviously his frame of mind has changed a little bit more. There's probably a lot more focus and concentration," Collins said. "He has to know now that he might be in there three, four days a week."
Meanwhile, Bobby Parnell continues to enter ballgames in a setup role during key situations.
"We're trying to do it in a process that works for everybody. I think there's going to be a time when Bobby pitches the ninth inning," Collins said. "I don't think there's any doubt that's going to come."
"As we've seen [in] the last three games Bobby Parnell has pitched they've been huge innings -- even though it's been the eighth inning -- because [of] who he's had to get out in those games and shut those games down, and he's done a good job doing it."