DaMarcus Beasley believes victory for Rangers in Sunday's Old Firm derby would make it tough for Celtic to win the SPL title.
Rangers head into the Ibrox showdown with a seven-point cushion over their fierce rivals, with Walter Smith's side also having a game in hand.
The reigning champions hold the edge in derby fixtures so far this season, winning 2-1 at home in October before drawing 1-1 at Celtic earlier this year.
And USA international Beasley feels another win for Gers would put a severe dent in Celtic's prospects of overhauling the current leaders.
"After that game there's still a lot of football to be played, but it will be tough for them to come back if we do win the match," Beasley told Sky Sports News.
"If we win two Old Firm games it will be pretty tough for them to come back and take the title from us."
Celtic will hand Robbie Keane his first experience of an Old Firm derby and Beasley feels the arrival of the striker on loan from Tottenham has helped to boost Scottish football's profile.
He added: "He's an asset to Celtic as well as to Scottish football. Scotland has been looking for a big name to come and sign for the league, and Robbie Keane is it.
"But I don't think one player can make a team. Obviously, he gives out motivation and inspiration, but Robbie Keane or anyone is not going to matter because we want to win the cup bad."