Matthews graduated from Warren Harding High School in Bridgeport, Connecticut, in 1977.

A 6 ft 1 in (1.85 m) point guard at the University of Wisconsin–Madison, he was selected by the Washington Bullets with the 14th pick of the 1980 NBA draft.

He played nine seasons in the league with the Bullets, Atlanta Hawks (two stints), Philadelphia 76ers, Chicago Bulls, San Antonio Spurs and Los Angeles Lakers.

Besides his NBA stints, he also played in the United States Basketball League, in the Continental Basketball Association and in Italy, spending the 1989–90 season at Ranger Varese before being called by the Hawks for one regular season match.

He had a stint in the Philippine Basketball Association (PBA), winning the best import award in 1991 for Ginebra San Miguel.