Updated at 6:43 p.m.
An enhanced MRI test of Gio Gonzalez's injured shoulder showed no structural damage, only inflammation, giving the Nationals reason to believe the left-hander's first career stint on the disabled list will be a short one.
Gonzalez, who was placed on the 15-day DL Sunday morning, was examined by an orthopedist and received relatively good news. Despite his recent struggles and the admission his arm didn't feel 100 percent healthy, he doesn't appear to be seriously injured.
"Tests came back great," manager Matt Williams said after the Nationals' 6-3 win over the Mets. "We'll build him back up, and we'll love to have him when he's ready."
Gonzalez will be shut down for the next four or five days to let the inflammation subside, but he could resume throwing after that. If all goes well, he could return once he's eligible to come off the DL on June 2.
"I don't have a great concern level for it right now, just because of the way Gio said he felt after the game," general manager Mike Rizzo said Sunday morning, before learning the MRI results. "The arm speed was there. The velocity was there. And that type of thing are all precursors to not to have that much worry."
Gonzalez had never spent any time on the DL in his seven major-league seasons, making 161 starts without ever missing a turn due to injury. But after two straight rough outings in the last week, it became clear something wasn't right.
The 28-year-old gave up seven runs in 4 1/3 innings last Sunday in Oakland, then allowed five runs in three innings Saturday against the Mets. The 12 combined earned runs allowed matched the most in his career in back-to-back starts, and the 7 1/3 total innings pitched were the fewest he has thrown since he was still emerging as a big-league starter with the Athletics in 2009.
Though his velocity was fine, Gonzalez admitted after Saturday's game he was having trouble with his arm slot, suggesting a shoulder ailment was preventing him from getting on top of the ball as he normally would. He first acknowledged some shoulder discomfort in an April 24 start, but had pitched well since then until this recent rough stretch.
"Uh, realistically, arm was dropping a lot," he said Saturday when asked directly whether anything was going on with him physically. "I guess we’ll see."
Rather than wait for the results of the dye-injected MRI, known as an arthrogram, the Nationals went ahead and placed Gonzalez on the 15-day DL before Sunday's game.
"[The doctor] gave him a strength test and all that stuff, and he passed a strength test," Rizzo said. "Combine having a little soreness yesterday with having a little soreness a month ago, we thought this was the prudent way to do it. Give him the arthrogram so we can see exactly what's going on in there. Put him on the DL for 15 days, give him some rest and relaxation, and once we find out what's on the MRI we'll take it from there."
The Nationals recalled right-hander Ryan Mattheus from Class AAA Syracuse for Sunday's game, giving them an eight-man bullpen for now, but they'll need someone to take Gonzalez's rotation spot on Thursday in Pittsburgh.
Right-hander Blake Treinen, who impressed in a spot start against the Dodgers earlier this month, is currently on schedule to pitch Thursday for Syracuse and would be a logical replacement for Gonzalez against the Pirates. Prospect A.J. Cole just tossed seven scoreless innings Saturday and boasts a 2.23 ERA at Class AA Harrisburg, so he would be on schedule as well, though he would need to be added to the club's 40-man roster.
Williams also mentioned right-hander Taylor Jordan, who has allowed only one run in 11 innings since his demotion to Syracuse, as a possible candidate. Jordan would be pitching on two extra days' rest if called up to start Thursday in Pittsburgh.
"We'll probably make that decision later on," Rizzo said. "We brought up an extra reliever until we need a starter, and we'll make the decision in a couple days."
Gonzalez becomes the eighth member of the Nationals' projected Opening Day roster to go on the DL in the season's first two months. Fellow right-hander Doug Fister, catcher Wilson Ramos, center fielder Denard Span and reserve outfielder Scott Hairston have since returned, but left fielder Bryce Harper, third baseman Ryan Zimmerman and first baseman Adam LaRoche remain sidelined.
"It's part of baseball," Rizzo said. "That's why you build depth in the organization. We're not going to (use an) alibi, we're not going to use it as an excuse, we haven't mentioned it. We've got our 25, this is our 25, and we're going to go to battle with those guys. It's time for guys to pick up the slack and play like they're supposed to play."