HOUSTON -- The arrival of Roger Clemens and Andy Pettitte to their hometown Astros before the 2004 season heightened the anticipation of the season in Houston. A loaded club now was poised to contend for its first World Series championship after luring Pettitte away from the Yankees, with Clemens coming out of retirement to join him.

The next two seasons were the greatest in Astros history, to that point, with Clemens and Pettitte both pitching at high levels as the Astros advanced to the National League Championship Series in 2004 and World Series in ’05. Both returned to finish their careers in New York following the ’06 season, but their places in Astros history were secure.

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The baseball resurgence in Houston in the mid-2000s came the year after closer Billy Wagner was traded to the Phillies, taking with him the club record for saves and legacy of “Billy the Kid.” The hard-throwing lefty was the club’s closer during a stretch in which they won four NL Central titles in five years (1997-99, 2001), only to come up short in the playoffs each season.

Clemens, Pettitte and Wagner headline the group of former Astros players who are on this year’s Hall of Fame ballot, which was released Monday. Players who appear on 75% of ballots in voting by the Baseball Writers’ Association of America will be inducted into the Class of 2021 on July 25. The voting will be revealed Jan. 26 on MLB Network.

Clemens is on the Hall of Fame ballot for the ninth year. Last year, he received 61% of the vote, which was his most, but only a small increase from the previous two years (59.5% in 2019 and 57.3% in ’18). He likely will need a sizable bump to put himself in contention to be elected in his final year of eligibility.

Pettitte, who went 37-26 with a 3.38 ERA in Houston, in the middle of his tremendous 15 seasons with the Yankees, is on the ballot for a third time. He appeared on only 11.3% of the ballot last year but has eight more years of eligibility for his support to increase.

Wagner, who played nine of his 16 seasons in Houston (1995-2003) and recorded 225 of his 422 saves, is appearing on the ballot for the sixth time. After receiving 16.7% of the vote in ’19, he nearly doubled his total last year when he appeared on 31.7% of the ballots.

Other former Astros on the ballot are Curt Schilling, Jeff Kent, LaTroy Hawkins and Bobby Abreu.

Schilling, who pitched with the Astros in 1991 before becoming a star with the Phillies and later the D-backs and Red Sox, has a real shot to get elected after getting 70% of the votes last year on his eighth time on the ballot. Kent (27.5% in his seventh year) and Abreu (5.5% in his first year) fell well short in voting last year.

There are nine former Astros in the Hall of Fame, but only Jeff Bagwell (2017) and Craig Biggio (‘15) have Astros caps on their plaques in Cooperstown, N.Y.