[5] In 1997 Knowles signed with Philadelphia Kixx and making it the highest contracted in the indoor game at 130,000 per season.
The Thunder moved to Denver at the end of the 1991–1992 season, and Knowles played three games there before being traded to the Milwaukee Wave.
He bounced back the next season, gaining ninety-four points, making him the second highest scorer on the Wave.
He continued his excellent play in the 1995–1996 season, earning his second Defender of the Year title and first team All NPSL recognition while racking up 123 points on 47 goals and 36 assists.
In February 1996, the MetroStars selected Knowles in the first round (ninth overall) in the league's Inaugural Player Draft.
On December 26, 1996, the Wave acquiesced to Knowles desires and traded him to the Cleveland Crunch for Glenn Carbonara, Todd Dusosky, Obi Moneme and cash.
On July 29, 1997, Knowles bought out the remaining three years of his contract with the Crunch and signed as a free agent with the Philadelphia KiXX.
At the end of the 1998 season, Knowles left outdoor soccer to concentrate on his more successful indoor career.