Terry Collins is aiming for 90 pitches from Johan Santana when the southpaw is activated from the disabled list to face the Braves on Saturday night at Citi Field.

The start will mark Santana’s first in the majors since July 20, when the southpaw surrendered six-plus runs for the third straight start.

Santana officially landed on the DL with a right-ankle sprain, which he suffered in his final first-half start, and which was complicated by Reed Johnson -- then of the Cubs, now of the Braves -- stepping on the ankle at first base. But team officials believe the ankle injury caused Santana to tax his shoulder and led to fatigue.

Collins said Santana touched 90 mph with his fastball in a three-inning rehab start Sunday with Brooklyn. Santana’s fastball averaged 87.5 mph in his final start before landing on the DL.

“He hasn’t hit 90 in a while,” Collins said. “So I think the rest has been good for him.”

As for the pitch count, Santana only threw 38 pitches during his outing with the Cyclones, but he upped the total to 90 by throwing in the bullpen at the Coney Island ballpark after departing the minor league outing.

The Mets will need to make a roster move to activate Santana. Garrett Olson might be the most logical player to drop, even with the need for a second left-hander in the bullpen while facing the Braves. Otherwise, Jeremy Hefner could end up back in Triple-A. Manny Acosta already has cleared waivers and been outrighted to the minors once this year, so he would be able to declare free agency if he cleared waivers.

As for Santana in 2013, Collins believe a more-normal offseason will make it easier for the southpaw to withstand the rigors of a full season.

“I really believe that with Johan now knowing that his shoulder is healthy, he doesn’t have to start the process so early as he did this past year,” Collins said. “He was playing long toss in December, throwing in January. This year he probably won’t start until Feb. 1, a throwing program. So it allows him to have a couple of months to rest things up. Next summer we may have to shut him down for a little while just to give him a blow. But I certainly think going into next year he’ll be in much better shape.”