HOUSTON -- With second baseman José Altuve nearing a return to the Astros' lineup, injured center fielder George Springer continues to progress as well. Springer fielded fly balls in center field Sunday morning at Minute Maid Park and is moving fluidly.

Astros manager AJ Hinch said Springer would run the bases Monday in Cincinnati, which could be his final hurdle being joining Altuve on a rehab assignment. Both Springer and Altuve have been out since May with strained left hamstrings, and Altuve later reported right leg fatigue.

“It is a good sign and it’s adding to what he’s doing to get ready to get back,” Hinch said of Springer, who’s been out since May 24. “We want him to do every single thing that we can think of that will help him get ready to play. We’re going to an extreme for him, basically because how long he’s been out where we can test him and get him to be as close to game-like [situation] as he can.”

Altuve, who’s been out since May 10, was scheduled to play back-to-back games at Triple-A Round Rock Sunday and Monday. He could be activated prior to Tuesday’s game against the Reds in Cincinnati.

“We’ll figure out whatever’s next,” Hinch said.