SARASOTA, Fla. — Orioles manager Buck Showalter feared that spring training was going too well when the team's daily medical report was always too quick of a read.

On Sunday, the Orioles had their first significant injury of the spring when right-hander Chris Tillman, the team's Opening Day starter in each of the past two seasons, didn't make his scheduled appearance in the intrasquad game because of tightness in his groin area that the Orioles called a “core muscle injury.”

Tillman was slated to pitch the first inning of Sunday's game at Ed Smith Stadium, but right-hander Kevin Gausman began the game instead. Orioles manager Buck Showalter said Tillman feels no pain when running or throwing, but the team wants to be careful to prevent further injury.

“Right now, it's precautionary, but who knows what” will happen? Showalter said. “If it lingers, we'll probably proceed with some other forms of trying to find out what it is. It probably wouldn't be as much of concern than if it was later in spring. Just want to be cautious with it right now. We'll see.”

Showalter said he hopes the problem will be resolved over the next few days but acknowledged that the severity of the injury is still unclear.

Tillman missed a start but didn't go on the disabled list in May 2014 with groin soreness. He also started the 2013 season on the 15-day DL with an abdomen strain he suffered during spring training, the only time Tillman has been on the DL in his major league career. He returned to the active roster five games into the season.

Head athletic trainer “Richie [Bancells] said he felt pretty good about it when he left last night,” Showalter said. “Said he got up last night and felt it at home. I think Richie was a little surprised it wasn't a lot better today.

“I don't want to paint it too cautious and then, I don't know. There's just a lot of unknown. Who knows where we go? Richie said if we get to the point where it didn't get better in a while — I don't know what a while is — we might do an MRI on it [to] see if there's something else there. But we're not there yet.”

Tillman recorded 200-inning seasons in 2013 and '14 but was hindered last year by an ankle injury he suffered in late July. Tillman missed just one start, but he had a 6.22 ERA in his final 11 starts upon his return.

If Tillman misses extended time this spring and falls behind in his preparation for the season — core injuries can be difficult for pitchers to overcome —the competition among other starters in camp would become much more intriguing.

Before the Orioles signed right-hander Yovani Gallardo last week to round out the rotation, four pitchers were competing for the club's final rotation spot: right-handers Mike Wright, Tyler Wilson, Vance Worley and Odrisamer Despaigne.

Wright and Wilson are two of the team's top majors-ready young starters, and they were used in starting and relief roles last year. Despaigne was acquired in a trade with the San Diego Padres on Feb. 4, before the Orioles acquired Gallardo.

Worley, who opened last season in the Pittsburgh Pirates' rotation, was claimed off waivers in October. Wright, Wilson and Despaigne can be optioned to the minor leagues, but Worley, who pitched a scoreless inning in Sunday's intrasquad game, has no options and will make $2.6 million this season.

During a spring training in which the focus has become the starting right field job and the final roster spots, any time Tillman might miss places more of a spotlight on starting pitching heading into the Orioles' Grapefruit League schedule.

Wright and Wilson will make their first spring starts in Tuesday's Grapefruit League opener against the Atlanta Braves in Lake Buena Vista. Wright will start and Wilson will follow, and Showalter said it's possible each could pitch more than one inning, depending on their pitch counts.

“They both bring something,” Showalter said. “Don't sell Tyler Wilson short. You talk about guys being trustworthy: He's a pretty trustworthy guy. He's not scared of the competition. He's going to throw it over. He might not wow you with stuff, but there's a reason why winning has followed him around. You can see why. He's not intimidated by much. That's where Despaigne comes in [also]. I've been impressed with him so far.”

eencina@baltsun.com

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