ARLINGTON -- It was impressive enough that Orioles pitcher Mitch Atkins tossed six innings of one-run baseball in his first career Major League start. That he did it against the defending American League champion Rangers in their home ballpark earned Atkins praise from both clubhouses Tuesday night, and it left the Orioles side still buzzing Wednesday afternoon.

"I thought he handled himself well from an emotional standpoint," Orioles manager Buck Showalter said of Atkins, who exited with the lead before Baltimore's bullpen coughed it up in a 4-2 loss.

"We will take it as a real positive," Showalter said. "I hope it turns out to be that. This guy is only 25 years old, he's younger than some of the guys that we have here that we are hoping are going to be long-term solutions."

Signed as Minor League free agent, Atkins was sidelined all spring with a left oblique strain and steadily worked his way through the Orioles' affiliates before Tuesday's promotion. He said he relieved about 20 text messages after his start and acknowledged it's been a whirlwind the last few days, as well as extremely gratifying to finally show the organization what he can do.

"It's an awesome feeling," Atkins said of rebounding from a disastrous start to the season. "It was the first time I had been hurt and it was probably the longest I had been on the DL, and so it was a little change of pace for me. It probably made me a better all-around player, just having that experience."

While the Orioles haven't set their rotation for this weekend, Showalter acknowledged that Atkins made a strong case and is a front-runner to start Sunday's game at Boston's Fenway Park. The Orioles will call on Jake Arrieta and Zach Britton, respectively, for the first two contests in the four-game set.

Showalter looks for turnaround from Vlad

ARLINGTON -- While some Orioles -- Nick Markakis and Mark Reynolds in particular -- have overcome slow starts to revert back to what manager Buck Showalter dubs their "track record," veteran slugger Vladimir Guerrero's declining production remains a concern.

The Orioles' cleanup hitter, Guerrero entered Wednesday with six homers and 28 RBIs, a pace that would put him well below last season's numbers with Texas, where he hit 29 homers and had 115 RBIs in 152 games. Guerrero has just one homer and five RBIs since June 1, and Showalter acknowledged that keeping him in the No. 4 spot isn't necessarily a guarantee moving forward.

Asked if he would let a future Hall of Famer like Guerrero just work his way out of his troubles, Showalter said, "To a point. He understands what a club needs in the four-spot and we also know what he's capable of doing. We have a lot of guys who have satisfied the trust we had in them and come back to norm, but he's had a pretty good sampling. And we know he's capable of more.

"We will see if it presents itself between now and the [All-Star] break, and if he can get it going."

Worth noting

• Orioles pitcher Alfredo Simon will leave the team on July 17 to go back to the Dominican Republic to tend to legal matters stemming from a New Year's Day shooting and imprisonment. Right now, the team is optimistic he will only be gone for a day or two.

• The game-time temperature for all three games in Teas was 100 degrees or more. The last time the O's played as many as three games in a season in 100-plus degree weather was 2006 (July 18, Aug. 1-2 all at home).

• J.J. Hardy's leadoff blast on Tuesday was his third game-opening homer this season, all of which have come in the last 25 games. The last Orioles hitter to lead off four games in a season with a homer was Brian Roberts in 2005.