Bagwell and longtime Astros second baseman Craig Biggio and teammate Lance Berkman were known as the "Killer B's", and the team experienced consistent success during their careers; Houston finished in first or second place in the NL Central division in eleven of twelve seasons from 1994 to 2005.

[11] He finished first in the league in hits and doubles, second in batting, OBP and OPS, fourth in walks, fifth in SLG, ninth in runs scored and tenth in RBI.

[12] Late in the 1990 season, the Red Sox, who were in search of relief pitching to improve their chances of making the playoffs, contacted the Houston Astros about Larry Andersen.

In his 2005 autobiography, One Pitch from Glory, Gorman noted that Boston already had Wade Boggs at the major league level at third base, and had rated prospects Tim Naehring and Scott Cooper higher than Bagwell on the organization's depth chart.

"[20] In spite of the unexpected detour early in Bagwell's professional baseball career, he blossomed in Houston, becoming one of the most accomplished players in Astros franchise history.

He spent his entire major league career in a Houston uniform and, along with teammate Craig Biggio in their 15 seasons playing together, were a prodigious offensive and defensive unit known as the "Killer B's", synonymous with the Astros throughout the 1990s and into the 2000s.

[b] During their 10 peak seasons from 1994 to 2003, they appeared in nine All-Star Games, won five Gold Gloves, ranked in the top five of the Most Valuable Player Award voting five times and averaged 226 runs scored.

[21] With an exaggerated and unusual batting style, Bagwell waited for each pitch in a low crouch, with legs wide open and knees bent nearly 90 degrees, appearing as if he was sitting on an invisible bench.

[22] Standing 6 feet tall (72 inches (180 cm)) and weighing 195 pounds (88 kg), he did not present the image of an imposing, home run-hitting giant that would cause pitchers to be very careful when he batted after he began his major league career.

By altering an approach to contact the pitch with topspin as he did when he arriving to Houston, Jaramillo taught Bagwell to hit with backspin, resulting in a soaring trajectory rather than nose diving.

However, a pitch from the Philadelphia Phillies' Ben Rivera broke the fourth metacarpal bone in Bagwell's left hand, ending his season prematurely.

[38] In the All-Star Game, Bagwell entered as a pinch hitter for starting pitcher Greg Maddux, singling off David Cone, and wound up collecting two hits in four at bats.

[58] According to journalist Dayn Perry, the earliest recorded reference to an Astros version of the nickname "Killer B's" encountered via a Google Search occurred that year.

[69] In 1998, Bagwell informed a Houston Chronicle reporter that he was using androstenedione (commonly referred to as "andro"), which at the time the United States Food and Drug Administration (FDA) classified it as a nutritional dietary supplement, finding it benign and authorized for non-medicinal purposes.

[76] As the "Killer B's" brand gained increased national attention, journalist Dayn Perry jocosely noted that in 1999 the Astros, "in pursuit of arcane history, used eight players whose last names began with 'B'",[59] including Bagwell, Paul Bako, Glen Barker, Bell, Sean Bergman, Lance Berkman, Biggio, and Tim Bogar.

[80] Nominated to his fourth career All-Star Game, Bagwell to that point in the season had scored or driven in 28.6% of the Astros' runs, the highest portion of a team's offense for which any one player in MLB accounted.

[85] Bagwell christened the team's 2000 move to Enron Field (later renamed Minute Maid Park) with the stadium's first-ever hit and first two runs driven in, in a 6–5 exhibition victory over the New York Yankees on March 30.

[86] His two-run, ninth-inning home run against Trevor Hoffman in San Diego on June 10 won the contest for Houston, 7–6, and stopped a 10-game road losing streak.

[7] Before a game against the San Diego Padres on August 27, he met with an 11-year-old bone cancer patient named Stephen Rael who asked him to hit a home run for him.

[7] During a 3–2 loss to the Montreal Expos on April 26, 2003, Bagwell's infield single gave him 2,000 hits for his career, joining Biggio as the only Astro to achieve this mark.

He scooped a ground ball batted from Hideki Matsui and relayed it to Billy Wagner covering first base, the final of a record six pitchers participating in the feat.

[105] ESPN's "The List" ranked Bagwell as the second-most underrated athlete of the top four North American professional sports leagues in August 2003, and Biggio third.

[107] He recorded his 200th career stolen base on August 30 against Cincinnati to become the tenth player in MLB history to reach that plateau while hitting 400 home runs.

Once possessing great ability to throw out the lead runner at third base ahead on bunt plays, Bagwell found it difficult to practice with the other infielders between innings.

[115] Concurrently, Bagwell's offensive production suffered, and pressure mounted on Astros management to bench the perennial All-Star; the club had started the season with a 15–30 won–loss record.

[116] Rendered unable to throw from his surgery,[117] Bagwell was activated in September as a pinch hitter,[118] and he played a symbolic role in the successful drive to capture their first-ever National League pennant and World Series appearance.

[123][124] Days earlier, orthopedic surgeon Dr. James Andrews had performed a physical examination on Bagwell and determined that he had become "completely disabled" and was unable to play baseball again.

[123][126] On March 28, Cigna rejected the claim, contending that because Bagwell had played during 2005 World Series he could not have become more disabled during the period of baseball inactivity characteristic of the offseason.

Speculation abounded that some baseball writers initially refrained from voting for Bagwell on the premise that he used performance-enhancing drugs, since most of his playing career took place during what is commonly referred to as "the steroid era.

[155] Per Baseball Reference, Bagwell's 79.6 Wins Above Replacement (WAR) ranks sixth-most all-time among first basemen, trailing only Lou Gehrig, Albert Pujols, Jimmie Foxx, Cap Anson, and Roger Connor.