Żewłakow was loaned to Belgium's KSK Beveren in October 1998 before signing – together with his twin brother Marcin – for Mouscron for a combined fee of €485,000.

Żewłakow went on to become a key player, helping the club reach the 2002 Belgian Cup final.

The next season, he lost his place but regained for the 2005–06 campaign as Anderlecht won the league again.

[4] In June 2011, Żewłakow joined Polish club Legia Warsaw on a one-year contract.

They became the first twins ever to play together for Poland when they were picked in the starting lineup to face France in February 2000 and were teammates at the 2002 World Cup.