Zach Thomas was a 5'11" linebacker from Pampa, TX who played collegiate ball for the Red Raiders of Texas Tech. He was a two-time All-American First-Team selection in his junior and senior seasons, and was also the Southwest Conference Defensive Player of the Year in 1995. Miami selected him in the fifth round of the 1996 NFL Entry Draft with the 154th overall pick. He would wear the number 54 jersey throughout his Miami career.
As a rookie in 1996, Thomas led Miami with 154 total tackles, more than doubling his nearest competition (Shawn Wooden, with 67). He started every game at middle linebacker, forcing two fumbles, recovering two more, collecting two sacks, and intercepting three passes, including one that he returned 26 yards for a touchdown in a week 12 victory over the Houston Oilers, 23-20. Miami finished the season with an 8-8 record, as the defense finished in the middle of the pack in most trackable categories. Thomas was a Pro Bowl alternate and a member of the All-Rookie team, as well as the AFC Defensive Rookie of the Year.
1997 would see Thomas start each of the 15 games in which he appeared with the Dolphins at middle linebacker. He again led the Dolphins with 128 tackles on the season. He also forced two fumbles, made half a sack and picked off a pass. The defense ranked fourth in the NFL with nine rushing touchdowns allowed. Miami earned a playoff berth with a 9-7 record.
In 1998, Thomas earned his first All-NFL First Team selection, along with cornerback Sam Madison. He made 137 tackles, leading the Dolphins and starting all 16 games. Miami led the NFL by allowing only 265 points on defense while making an NFL high 29 interceptions. Three of them were by Thomas, who returned two of them for touchdowns. Miami earned another wildcard position with a 10-6 record.
Thomas was selected to his first ever Pro Bowl following the 1999 season, leading the team with 133 tackles while starting every game. He was also one of three Dolphins to represent on the All-NFL First Team. He also made one sack, forced a fumble, and intercepted a pass. Miami's defense placed fifth in the NFL with 4,404 total yards allowed, leading the AFC with only six rushing touchdowns allowed. Their 9-7 record gained them access to the playoffs for the third season in a row.
In 2000, Thomas missed five games due to injury, yet still managed to lead the Dolphins with 99 total tackles. He was invited to his second Pro Bowl, as the Dolphins returned to the playoffs by winning the AFC East at 11-5. Miami's defense placed third in the NFL by allowing 226 total points on the campaign. The team led the NFL with 28 interceptions.
2001 would see Thomas make his third consecutive Pro Bowl, playing every game but one for the Dolphins at middle linebacker. He had 155 tackles through the season for Miami, as the team finished at 11-5. He also made three sacks, two interceptions, and forced two fumbles. He also scored his fourth career touchdown, returning a Tennessee Titans interception 34 yards in a season opening 31-23 victory. The defense allowed an NFL fifth best total 4,608 yards.
In 2002, Thomas made his third All-NFL first team and his fourth Pro Bowl. He led Miami with 156 total tackles, also making a half sack, an interception and a fumble recovery. Miami's 9-7 record was not enough to return the team to the playoffs for what would have been a record six straight seasons (Miami has made the playoffs in five consecutive seasons three times). The Dolphins led the AFC by allowing only 301 points and 4,656 yards on the season.
It was more of the same for Thomas in 2003, leading the Dolphins with 153 tackles while starting every game but one. He collected three interceptions, recovered two fumbles, forced one fumble and recorded a sack. He made his fifth straight Pro Bowl and again was selected to the All-NFL First Team. Miami went 10-6, failing to make the playoffs for the second season in a row with a winning record. Miami allowed an NFL third lowest 261 points on the campaign. With 12 touchdowns allowed on pass defense, the team placed second in the league.
2004 would see Thomas miss the Pro Bowl for the first time in six seasons, as he started each of his 13 appearances at middle linebacker. He again led the Dolphins with 145 tackles, also making two sacks. The Dolphins finished at 4-12, only the third losing record the team had suffered since the AFL/NFL merger in 1970. Somehow, Miami's pass defense led the AFC by allowing only 2,592 yards on the season.
In 2005, Thomas would return to the Pro Bowl for his sixth appearance. He led the team with 162 tackles while starting 14 of Miami's games. By this point, Miami had mastered the art of missing the playoffs with a winning record, going 9-7. Miami led the AFC, sacking the opposing quarterback 49 times on the season, twice by Thomas.
Thomas recorded a career high 165 tackles in 2006, starting every Miami game. Miami finished the season 6-10, but Thomas made his seventh Pro Bowl appearance, also earning first-team All-NFL honors for the fifth time. Miami allowed an NFL fifth lowest 283 points on the season, also allowing an NFL fourth best 4,625 yards.
2007 would see Thomas start only three of his five appearances for Miami, spending the rest of the season injured. He played the 2008 season for the Dallas Cowboys before signing with the Kansas City Chiefs for the 2009 season. Thomas did not play past the preseason, and eventually signed a one day contract to finish his career a Miami Dolphin. He is Miami's all-time leader with 1,639 tackles, His 1,733 total tackles are more than any linebacker currently in the Hall of Fame.