13. Kevin Willis
Willis played two decades in the NBA before joining the Mavericks. The seven-footer was the 11th overall pick in 1984 after four years of college basketball. He became an All-Star with the Hawks in a season where he averaged 18.3 points and 15.5 rebounds per game. Willis spent a decade in Atlanta before bouncing around to six different teams.
He won a championship with the Spurs in 2003 and returned to Atlanta in 2004. The 42-year-old played 29 games with the Hawks and appeared retired before the Mavs gave him one final chance.
Dallas had an open roster spot and needed a big man late in the 2007 season. They were cruising to the best record in the league and decided to take a chance on Willis. The 44-year-old had not played in virtually two years. He appeared in just five games with the Mavericks and produced 12 total points and eight rebounds.
Dirk Nowitzki won MVP, but the Dallas Mavericks were shockingly upset in the first round of the playoffs by the “We Believe” Warriors. Kevin Willis did not see the floor in the postseason and played his final NBA game with Dallas. The Mavs' options were limited, but it was still shocking to see them add a 44-year-old to round out their roster.