Mets manager Terry Collins told ESPN Wednesday that starting pitcher Zack Wheeler will work with pitching coach Dan Warthen to avoid tipping off pitches during Wheeler's next bullpen session.

Wheeler surrendered four runs over 5 1/3 innings in his second big-league start Tuesday against the White Sox. Collins said the Mets noticed that Wheeler was tipping his breaking balls during his previous start. He owns a 3.18 ERA through two starts.