CELTIC winger James Forrest believes rivals Rangers will provide their biggest challenge in the Ladbrokes Premiership this season. 

The two Glasgow giants meet at Ibrox on Saturday in their first clash of the season, with the champions currently topping the table and sitting four points ahead of third-placed Gers.

Forrest has been in superb form so far this season and added another two goals to his tally last night during a 4-0 Betfred Cup quarter-final win over Dundee.

Read more: Celtic boss Brendan Rodgers expects Jozo Simunovic and Moussa Dembele to be back for Rangers game

When asked after the game if Pedro Caixinha's side will be Celtic's closest challengers, he told BBC Scotland: "Definitely. They've spent a good wee bit in the summer, but we can't focus on that. We just have to concentrate on ourselves.

"When you play Rangers at Ibrox or at Celtic Park, it's always going to be a hard game, but we go into it on the back of some good results and good performances.

"I don't think you can ever really get used to it - I don't think anyone can.

"The atmosphere at both grounds and at Hampden is always first class, always really hostile.

"As a player, it's just one where you want to play in the big games and that one is definitely up there with the biggest."