HOUSTON -- Orioles catcher Matt Wieters isn't looking beyond Friday, when he is scheduled to throw for the first time in more than three weeks, but he's still encouraged by the progress with his right elbow.

"It’s gotten a lot better over the last few days, which is what we were waiting on," Wieters said Thursday. "Now it's just a matter of going through the throwing progression and hopefully everything keeps getting better.

"Every movement that gets me back towards getting on the field is good."

The All-Star and Gold Glove catcher will test his arm with a throwing session before Friday’s game.

“It'll be a distance and number of throws. I’m sure it won’t be anything too stretched out,” Wieters said. “We got a whole throwing program, but the trainers know it better than I can. If everything goes well, we are going to pick up a ball tomorrow.”

Wieters hasn’t caught since May 4 and hasn’t played in a game since May 10. He served as a designated hitter for four games before being shut down, because he only felt the pain when he threw. Wieters also received a platelet-rich plasma injection in his elbow on May 12.

The throwing session will be the first step Wieters takes in truly gauging whether he can return this season. The club hopes to make a decision whether Wieters will need season-ending surgery by July 1.

Wieters, who has continued to receive treatment for the injury, added that the emphasis will be on throwing right now before returning to hitting.

“Throwing will be the more important thing to see,” he said. “Swings will be a lot easier to catch up on than the throwing will be.”

Wieters, who leads all American League catchers in All-Star voting, was hitting .308 with five homers and 18 RBIs in 26 games before going on the DL.

Meanwhile, as the Orioles open up a four-game series against the Houston Astros, their starting lineup has a slightly different look. Hot-hitting Steve Pearce is in the No. 2 spot, and usual two-hole hitter Manny Machado is batting seventh.

Pearce is hitting .351/.393/.614 with four homers and 11 RBIs in 19 games in May. He also hitting .340/.377/.580 with three homers and 9 RBIs against right-handed pitching this season.

Machado hasn’t batted this low since the end of his 2012 rookie season.

Here are the starting lineups:

Orioles
Nick Markakis RF
Steve Pearce LF
Adam Jones CF
Chris Davis 1B
Nelson Cruz DH
J.J. Hardy SS
Manny Machado 3B
Ryan Flaherty 2B
Nick Hundley C
Ubaldo Jimenez RHP

Astros
Jose Altuve 2B
George Springer RF
Dexter Fowler CF
Jason Castro C
Matt Dominguez 3B
Chris Carter 1B
Alex Presley LF
Robbie Grossman DH
Jonathan Villar SS
Brad Peacock RHP