Orioles manager Buck Showalter shot down a reporter’s theory yesterday that the offensive outburst in the seventh inning at Yankee Stadium may have relaxed his hitters.

“We’ve got (Justin) Masterson tomorrow,” Showalter replied. “You think we’ll be relaxed and confident? That’s why people are playing meaningful games this time of the year, because they’ve got good pitchers you’re going to see every day.”

Masterson certainly belongs on that list. He’s 14-9 with a 3.49 ERA, and he’s the latest challenge to a team that starts the day trailing the Rays by three games for the final wild card spot.

Masterson is 6-4 with a 4.71 ERA in 13 career appearances against the Orioles, including nine starts. He allowed six runs and six hits in 6 1/3 innings in a June 25 game at Camden Yards.

Right-handers are batting .187 against Masterson this season and .218 in his career, so you’d expect Showalter to stack his lineup with left-handed hitters. However, Danny Valencia is 6-for-16 against Masterson. Michael Morse is 0-for-3.

Small sample size.

The most interesting decision involves Alexi Casilla, who’s 10-for-29 with a double, triple, two home runs and 11 RBIs against Masterson. Brian Roberts is 5-for-17.

Who starts at second base?

Chris Davis is 4-for-12 with two doubles and a home run. Nick Markakis and Matt Wieters are a combined 8-for-46 - each with four hits - but they figure to be in today’s lineup.

Meanwhile, the Orioles will make a roster move today by adding left-hander Zach Britton, who was scratched from his start at Triple-A Norfolk.

Before yesterday’s game, Showalter downplayed the possibility of adding a pitcher in Cleveland. However, Wei-Yin Chen lasted only four innings, Kevin Gausman isn’t available today after pitching on back-to-back days and the Orioles could use a fresh arm.

The Tides have one game remaining and a one-game lead over Rochester in the wild card race, and they’re handing the ball to newly promoted right-hander Mike Wright, who was 11-3 with a 3.26 ERA in 26 starts at Double-A Bowie.

The Orioles selected Wright, 23, in the third round of the 2011 First-Year Player Draft out of East Carolina University. He tends to get overlooked among the organization’s pitching prospects, but he deserves the same recognition as Kevin Gausman, Dylan Bundy and Eduardo Rodriguez.

Catcher Michael Ohlman isn’t in Single-A Frederick’s lineup today, so he’ll win the Carolina League batting title with a .313 average. Another guy who’s stock has really risen this year.