"I think we're being a little bit conservative given who it is," Ricco said.
Both Ricco and manager Terry Collins said they do not consider the injury serious, and that Wheeler should only miss one start. But it comes at a most inopportune time for Wheeler, who had turned around his rocky start to the season by going 2-0 with a 1.35 ERA, 19 strikeouts and three walks over his last three outings.
Both of the Mets' two top prospects will visit New York this week, with catcher Travis d'Arnaud also scheduled for a checkup on his fractured left foot. d'Arnaud is expected to miss at least another month.
Anthony DiComo is a reporter for MLB.com. Follow him on Twitter @AnthonyDicomo. This story was not subject to the approval of Major League Baseball or its clubs.