TORONTO -- The calendar has flipped to September, which means rosters around the Majors are expanding beyond the 25-player limit. Astros manager AJ Hinch said the team’s September call-ups will come in waves -- but the first wave hasn’t hit just yet.

“We’ll have a couple guys tomorrow [in Milwaukee], then we’re expecting a couple guys when we come home for the Thursday game against the Mariners,” Hinch said Sunday. “But until we let the players know, I’m not going to address it.”

Among the expected call-ups is top-ranked prospect Kyle Tucker (No. 12 in MLB Pipeline's Top 100), an outfielder with 34 home runs, 30 stolen bases and a .909 OPS at Triple-A Round Rock this season. Tucker managed just a .141 batting average in 28 games with Houston last season.

The Astros’ lone roster move Sunday was activating reliever Josh James from the 10-day injured list (right shoulder soreness) before the game against the Blue Jays at Rogers Centre.

James, who hasn’t pitched in the Majors since July 21, has a 4.73 ERA in 51 1/3 innings this season. While rehabbing, he worked on shortening his delivery and “staying inside 90,” as he described it. That means keeping his arm angle from extending past 90 degrees at the elbow, so he can improve his control.

With 5.4 walks per nine innings this year, James has the highest walk rate on the team. But he also has the highest strikeout rate (14 per nine innings), which should help in light of injuries to fellow relievers Collin McHugh, Aaron Sanchez, Brad Peacock and Ryan Pressly.

“As we’ve had a couple of our guys go down, it starts to bring more important innings available,” Hinch said. “And Josh James being a true weapon when he’s right and when he’s in the strike zone -- he’s throwing in the mid to upper 90s -- we’ve seen what kind of success he can have missing bats.”

Here’s a brief look at Astros prospects to look out for now and in the seasons to come:

Arrival: Infielder Abraham Toro, the Astros’ No. 6-ranked prospect by MLB Pipeline, made his Major League debut in August and could push to be a bat off the bench next year. Houston’s infield is set for at least one more year with Yuli Gurriel at first, Jose Altuve at second, Carlos Correa at shortstop and Alex Bregman at third, but Toro is a talented hitter who has a plus arm and good hands.

Breakout: Right-hander Brandon Bielak could be in the mix for a spot in Houston’s rotation going forward after a solid 2019 season. The Notre Dame product has gone 11-4 with a 4.22 ERA through 23 games (20 starts) split between Double-A Corpus Christi and Round Rock. Bielak’s fastball sits at 91-94 mph, and the Astros have tinkered with his breaking pitches, switching him to a traditional curveball and tightening his slider. He has also shown good control and is durable despite a smaller frame.

Something to prove: Right-hander Forrest Whitley, ranked as the Majors' No. 16 overall prospect by MLB Pipeline, is finishing the year strong after a rough few months. After getting rocked at Triple-A to start the year, Whitley was sent to the Rookie-level Gulf Coast League, then eventually to Double-A. In Wednesday's outing for Corpus Christi, he allowed one hit in 5 1/3 shutout innings, striking out eight and walking four. Whitley has 33 strikeouts and 18 walks in 20 2/3 innings at Double-A this year.​ He will return to the Arizona Fall League, where he was named the league’s best pitching prospect a year ago.

Name to watch: Right-hander Cristian Javier, signed out of the Dominican Republic in June 2015 for $10,000, has bloomed the past couple of years. Despite working with a fastball that’s 88-93 mph, he gets strikeouts with a pair of effective breaking balls. He went 6-3 with a 2.07 ERA in 17 outings (11 starts) at Corpus Christi with 114 strikeouts in 74 innings before being promoted to Round Rock in August. He has a 1.64 ERA and 16 strikeouts through two starts at Triple-A.

Yuli scratched late
Yuli Gurriel was scheduled to bat fifth and play first base on Sunday, but he was scratched less than two hours before the game with a left elbow contusion. Gurriel was hit by a pitch during Saturday’s game, causing the contusion.

Gurriel has reached base in 51 of 56 games since June 23, with 22 home runs, 65 RBIs and a 1.200 OPS in that span.