Cassell, 32, signed a three-year, $17 million US contract extension on Thursday that makes him a Milwaukee Buck through the 2005-06 season.
Cassell had one year remaining on a six-year, $21 million US pact he signed with the New Jersey Nets in 1997.
But at an average annual stipend of $3.5 million US, he was earning less than backup point guards Derek Fisher of the Los Angeles Lakers and Charlie Ward of the New York Knicks.
"Sam has been a very important part of our success and his extension has been one of our top priorities," Bucks general manager Ernie Grunfeld said.
Cassell is averaging 20.2 points and 6.9 assists per game in 42 appearances this season, his ninth in the NBA.
He has averaged 15.2 ppg and 6.2 apg in 552 games with the Houston Rockets, Dallas Mavericks and Phoenix Suns.
Cassells is currently considered one of the league's premier point guards, having won league titles in his first two years with the Rockets.
"In Sam, we have one of the top point guards in the NBA," Grunfeld said. "He is a tremendous clutch player with playoff experience who has excelled for us at the most important position on the floor."
Cassell was traded to Milwaukee by New Jersey on Mar. 19, 1999, in a three-team transaction involving fellow star point guards Terrell Brandon and Stephon Marbury.
