PORT ST. LUCIE, Fla. -- Entering Spring Training, the Mets couldn't be sure of Steven Matz's health. It never crossed their mind that he might be healthy but ineffective.
Now, they can't ignore that possibility. Matz allowed five runs for the second consecutive outing on Sunday, spiking his ERA to 54.00 in the Mets' 7-3 loss to the Nationals -- and leaving the left-hander searching for answers.
"Even though it's Spring Training, you want to see results," Matz said. "You don't want hitters to get hits off you. I don't care if it's a live BP or in a game or in the regular season. So it's definitely frustrating."
Coming off surgery to reposition the ulnar nerve in his pitching elbow, Matz continues to say this is the healthiest he has felt in years. And while most of the five hits off him were struck softly on Sunday, Matz also walked two batters for the second consecutive start. He bemoaned his inability to pitch down in the zone, while manager Mickey Callaway said Matz lacked conviction in his delivery.
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The results were similar to last summer, when Matz posted a 6.08 ERA in 13 starts. But back then, he was pitching through at least some level of discomfort, which he insists is no longer the case.
"It's key for him to have some success in Spring Training going into the season," Callaway said. "We're not worried at this time. He'll have some success. He's got good stuff and he'll get through it. Just a little bump in the road right now."
Though Matz is ostensibly competing for a rotation spot, team officials entered Spring Training assuming he would break camp in the starting five. Two bad starts early in spring won't change that, though Matz knows he must demonstrate improvement before March ends.
"You don't let it linger," Matz said. "It's Spring Training, so you've got to work on stuff out there, not necessarily attack guys the way you would during the season. To not pay attention to results is hard, but tomorrow's a new day. I've just got to keep working."
Baby steps
Infielder T.J. Rivera, who underwent Tommy John surgery in September, began throwing late last week for the first time since his operation. Currently, Rivera is only throwing up to 45 feet as he works his arm back into game shape.
"The first time, it felt weird," Rivera said. "It's something I've done for so long, but you have to get back into that routine. The second time felt way more normal."
The Mets recently placed Rivera on the 60-day disabled list, ruling him out as an option before the end of May.
Powering up
Batting third and fourth for the Mets on Sunday, Jay Bruce and Todd Frazier both hit their first Spring Training homers, giving the Mets a taste of what they hope the middle of their batting order can do this summer.

"Any time you hit the ball hard, it feels good," Bruce said. "I'm not necessarily concerned with home runs in Spring Training, or anything like that. I'm never really concerned with home runs at all, to be honest with you. They just kind of happen."
Callaway has hinted that Yoenis Cespedes will hit second for the Mets during the regular season, freeing Bruce and Frazier to slot in behind him.

Injury updates
An examination of shortstop Amed Rosario's sore left knee revealed nothing more than what the team is calling "irritation." Rosario is day to day, with plans to return to the lineup on Tuesday.
First baseman Dominic Smith also continues to progress from a strained right quadriceps, taking batting practice for the first time Sunday.
Camp battles
Matt Purke, who hopes to make the Mets' Opening Day roster as a second lefty in the bullpen, tossed a perfect sixth inning to record his second scoreless outing of spring.
Up next
After hitting 96 mph in his first spring start, Matt Harvey will look to lengthen out when he takes the mound Monday for a 1:10 p.m. ET game against the Tigers on MLB.TV. Back-end relievers Jeurys Familia and AJ Ramos are also scheduled to pitch in the game.