In , Viola made the All-Star Game for a third time after posting an 11–5 record in the first half of the season. However, as the Mets collapsed in the second half of the year to finish with a 78–84 record, Viola collapsed with them and went 2–10 in his final 12 decisions. His last win came in his second-to-last start with the Mets on September 29 at Shea Stadium against the Philadelphia Phillies. He became a free agent after the 1991 season when the Mets opted not to resign Viola.