NEW YORK >> Matt Harvey has symptoms consistent with thoracic outlet syndrome, and the struggling New York Mets star could be facing season-ending surgery to treat a serious condition that has jeopardized the career of other major league pitchers.
General manager Sandy Alderson announced the diagnosis Thursday after Harvey was examined in St. Louis by a specialist, Dr. Robert Thompson. Alderson said a decision on surgery is likely to come in the next few days before the All-Star break.
Thoracic outlet syndrome is a condition caused by the compression of nerves, blood vessels or both in the area between the neck and armpit. After his start Monday, the 27-year-old Harvey complained of some common symptoms, which include numbness in fingers and shoulder discomfort.
The former ace was seen by Mets doctors, referred to Thompson for further examination and placed on the 15-day disabled list Wednesday, retroactive to Tuesday.
Another temporary treatment option is a "nerve block" that might help Harvey return to the mound fairly quickly, but surgery is probably inevitable at some point and the operation usually requires a four-month recovery period, Alderson said.
Harvey had been scheduled to start Saturday night at Citi Field against Max Scherzer and the NL East-leading Washington Nationals. Right-hander Logan Verrett (3-5) will pitch in his place and could get a chance to hold down that spot in the rotation.
"We'll evaluate it, but right now he'd be the guy we would lean toward," New York manager Terry Collins said.
Complicating matters for a suddenly fragile Mets rotation, right-hander Zack Wheeler has had several setbacks in his recovery from Tommy John surgery this year. The team initially targeted the All-Star break for his return, but Wheeler hasn't even thrown off a mound yet and there's no longer a definitive timetable for his expected progress.
Alderson said he is "confident, not certain" that Wheeler will be back this season.
The defending NL champions trailed Washington by four games going into the opener of their four-game series Thursday night.
Harvey is 4-10 in 17 starts with a 4.86 ERA — 78th among 97 qualifying pitchers in the major leagues. He has given up 111 hits in 92 2/3 innings, with 76 strikeouts and 24 walks.
Harvey hasn't won since May 30, but he and the team insisted all season he was healthy. The Mets reiterated Thursday that the right-hander didn't complain of any symptoms until after Monday's outing, when he was tagged by Miami for six runs — five earned — and 11 hits over 3 2/3 innings before the Mets rallied from a 6-0 deficit to win.
After missing the 2014 season following Tommy John surgery, Harvey went 13-8 with a 2.71 ERA last year in 29 starts covering a career-high 189 1/3 innings.
Late in the season, agent Scott Boras said doctors recommended that Harvey be limited to approximately 180 innings in his first year back from reconstructive elbow surgery. At first, the star pitcher was noncommittal about going beyond that total — generating a firestorm in New York with the Mets in the middle of a playoff race.
Soon after, he announced he planned to pitch in October.
Harvey threw an additional 26 2/3 innings in the postseason, going 2-0 in four outings while helping the Mets to their first pennant in 15 years.
He was working on a shutout in Game 5 of the World Series against Kansas City when he pushed to pitch the ninth inning and talked Collins into it. Given a chance to go back out to the mound, Harvey faltered and the Royals rallied to win the championship.
Selected seventh overall by the Mets in the 2010 amateur draft out of North Carolina, Harvey blossomed into one of baseball's best pitchers three years later and started the 2013 All-Star Game on his home mound at Citi Field.
To replace Harvey on the roster, the Mets recalled right-hander Seth Lugo from Triple-A Las Vegas on Wednesday following their 4-2 victory over Miami.