CINCINNATI - Zack Wheeler showed no signs of fatigue even as he entered the homestretch of his first full season in the big leagues. And Jeurys Familia looked fresh after a four-day breather to break up his unusually busy summer.

This proved particularly relevant Sunday as the Mets held off a ninth-inning rally to beat the Reds, 4-3.

The fate of manager Terry Collins remains up in the air, according to a source, and some voices within the organization have grumbled about Collins' use of the team's young arms. But Collins appeared to be more judicious Sunday.

Wheeler, 24, has been pushed to more than 110 pitches in an outing 13 times this year, but Collins pulled him Sunday after six innings (99 pitches) in which he gave up one run.

"We've got to finish the season with this guy healthy," Collins said. "He's shown way too much promise here in this season. We cannot go into [next] season with a sore shoulder or a sore elbow."

Behind four unearned runs, and homers by Curtis Granderson and Anthony Recker, Wheeler (10-9) lowered his ERA to 3.38. "Honestly, I feel fine bodywise," he said. "You really couldn't ask for anything more."

Familia, 24, ranks third among NL relievers with 692/3 innings in his first full season. But he looked fresh, striking out the side in a perfect eighth.

The Reds nearly rallied from a three-run deficit in the ninth against closer Jenrry Mejia, who started the inning by allowing a solo homer by Jay Bruce and then gave up a double by Jack Hannahan and an RBI single by Ryan Ludwick.

With the Reds down to their last out, Todd Frazier hit a slow roller to third base, where David Wright charged it and made a strong throw. Frazier initially was called out to end the game, but a replay review overturned the call, loading the bases and giving the Reds one more chance. But Mejia struck out Devin Mesoraco on three pitches and picked up his 24th save.