WASHINGTON — Phillies manager Rob Thomson said Thursday that he will utilize a six-man rotation beginning this weekend when Aaron Nola returns from the injured list.

Nola is lined up for the series finale Sunday at Washington. The 32-year-old right-hander is coming back from a right ankle sprain.

Left-hander Ranger Suárez takes the mound Monday against the Mariners. The NL East leaders also have ace right-hander Zack Wheeler, lefties Cristopher Sánchez and Jesús Luzardo and right-hander Taijuan Walker.

Thomson said he isn’t sure how long he is going to use the six-man rotation.

“Once for sure and then we’ve got some other ideas how to attack this thing as we move forward,” he said.

Philadelphia starters lead the majors with 687⅓ innings pitched. Sánchez is up to 150⅔ innings, and Wheeler is at 144⅔.

“Just getting some of these guys some extra rest ’cause we’ve been grinding on them pretty hard all year,” Thomson said before the opener of a four-game set against the Nationals. “The one downside to it is you’ve got to take somebody out of your bullpen, so you’re a little short there but we’ll just have to figure it out.”

Nola hasn’t pitched in the majors since May 14. He posted a 2.19 ERA in three rehab starts with Triple-A Lehigh Valley while striking out 17 batters in 12⅓ innings.