"I was surprised," Scheppers said. "It was like 10 minutes before I got out there that I found out. At that point I just want to go out there and throw strikes, protect the guys and let my team go out there and make some plays for me."
Scheppers, who missed the first five months of the season while recovering from surgery on his left knee, did that in his fourth outing since coming off the disabled list.
The Rangers were eager to give Dyson, Keone Kela and Jake Diekman the night off after they all worked in Monday's 12-inning victory. That's why Scheppers was on the mound in the ninth inning trying to protect a 3-2 lead.
He did just that against the top of the Astros' lineup. He retired George Springer on a fly to deep center and struck out Alex Bregman. That left Jose Altuve, who is leading the American League in hitting, and Scheppers retired him on a line drive to center to end the game.
"I'm proud of him," Rangers manager Jeff Banister said. "Proud of how he composed himself and how he held himself together. Solid fastball ... the velocity was there, the movement is there. He got the three outs we needed."
Scheppers saved it for Alex Claudio, who worked a scoreless eighth for his fourth win of the season. The save was Scheppers' first since Aug. 6, 2013.
That was when he was one of the top relievers in the American League. Now he has become an integral part of the Rangers' bullpen again.
"I feel like I'm still alive and pitching," Scheppers said. "I worked really hard this year to get where I'm at right now and I just want to be a part of special at this point."
T.R. Sullivan has covered the Rangers since 1989, and for MLB.com since 2006. Follow him on Twitter @Sullivan_Ranger and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.