Joe Ledley knows he is going to have to be 'on his toes' when Wales meet British rivals Scotland in their crucial World Cup qualifier.
Ledley and Adam Matthews could directly face Parkhead team-mates Scott Brown and James Forrest as both countries look for their first win in Group A on Friday.
And the former Cardiff midfielder is anticipating a tough night against in-form Celtic skipper Brown.
"There will be a lot of battles in the game," said Ledley. "James up against Adam, and me up against Scott Brown, so there will be key battles and we will see who comes out on top.
"We play against each other in training every day and we know each other's strengths and weaknesses so it is going to be a good game and we look forward to it.
"Scott is fantastic. He is one of our better players this season. He drives the players on and tries to attack as well.
"I am going to be on my toes and it is going to be a difficult evening for me."