He was a four-year starter and the Davenport North team made the state tournament his junior and senior years but did not reach the championship.

Davis played one season at the University of Iowa before being selected by the Charlotte Hornets in the first round of the 1998 NBA draft, as the 21st pick overall.

Davis injured his ankle and knee with the Heat and only played a total of seven games for them, and was eventually sent to the Cleveland Cavaliers in a three-team deal involving the Toronto Raptors a year later on October 26, 2001.

Davis was re-signed to a six-year deal by the Cavaliers on August 21, 2002, but his time in Cleveland was marked by disputes with coach Paul Silas.

[3] With Cleveland leading 120–95 and less than 7 seconds remaining, Davis was one rebound short of his first career triple double, and he deliberately tossed an inbound pass off his own rim and caught it in attempt to receive credit for a rebound, but shots taken at one's own basket do not count as official field goal attempts.

However, in the face of a national outcry, the Cavaliers fined him an undisclosed amount for unsportsmanlike conduct, and the play led to Davis being nicknamed "Wrong Rim Ricky" in Cleveland.

[5][6][7] On December 15, 2003, Davis was traded along with Chris Mihm, Michael Stewart, and a second round draft pick to the Boston Celtics in exchange for Tony Battie, Eric Williams, and Kedrick Brown.

Boston was criticized for acquiring him via trade due to Davis's reputation of selfishness, but he became a more consistent player and a fan-favorite in the city.

[11] He was waived by the Clippers on February 16, 2010, to make room for newly acquired guard Steve Blake and forward Travis Outlaw.