Correa, placed on the 10-day disabled list with lower back soreness on June 26, was originally slated to return to action for the Astros' 11-game homestand that preceded the All-Star break and continues with the opener of a four-game series with the Oakland Athletics on Monday.
Instead, Correa remains sidelined with no clear view of when he will rejoin the club. The Astros (61-31) improved to 9-3 with Correa unavailable after their 2-1 win over the Chicago White Sox.
The timing of the injury likely cost Correa a shot at making his second American League All-Star team. He was second in the voting behind the Baltimore Orioles shortstop Manny Machado with a .268/.352/.480 slash line, 13 home runs and 49 RBIs. His 129 wRC+ is fifth among AL shortstops.
"I don't think we're going to give up yet. There's a lot of games (left)," Astros manager A.J. Hinch said. "It's easy to put it on paper and wonder, 'Hey, we'll just give him another week off and we'll see what happens. And then you look at how many games there are and how many at-bats there are and the progress he can make. It's imperative for us to stay patient."
Right-hander Gerrit Cole (9-2, 2.70 ERA) will start the series opener.
He is 2-1 with a 3.51 ERA in four career starts against the Athletics, including two victories (with a 3.86 ERA) in three starts this season.
Cole has 27 strikeouts in 18 2/3 innings against Oakland this season and is only nine shy of matching the club record set by Mike Scott in 1986 of 167 strikeouts before the All-Star break. Cole has allowed at least four earned runs in three of his last five starts after not doing so in his first 13 appearances this season.
Right-hander Frankie Montas (4-2, 3.83) will start for Oakland on Monday.
Montas has faced the Astros three times in his career, going 0-1 with a 12.27 ERA, including a start on June 14 when he allowed seven runs (five earned), 11 hits and four walks in 5 1/3 innings of a 7-3 loss at Oakland-Alameda Coliseum. That marked Montas' first career start against the Astros.
Oakland (50-40) claimed the rubber match of its series on Sunday in Cleveland, blanking the Indians 6-0 to improve to 16-4 in its last 20 games.
The Athletics had dropped four consecutive games before embarking on their current run, including being swept at home by the Astros in a three-game series in mid-June. Houston outscored Oakland 26-11 in that series.
The Athletics have caught fire despite a laundry list of injuries.
Right-hander Paul Blackburn landed on the 10-day disabled list Sunday with tennis elbow, joining four other starters on the DL: Trevor Cahill, Daniel Gossett, Daniel Mengden and Andrew Triggs. Cahill could rejoin the team in Houston on Tuesday.
Left-hander Brett Anderson returned from the DL and twirled five shutout innings in Cleveland for his first win of the season and first for Oakland since 2013.
The A's enter 10 games above .500 for the first time since the end of the 2014 season when it lost to Kansas City in the wild-card game.
"We don't care who we play," Oakland manager Bob Melvin told reporters. "We know we have seven games before the break. We want to finish up strong, so it doesn't matter who we're playing."