Manchester United legend Roy Keane says Odion Ighalo has made a difference to Anthony Martial.

Keane believes Ighalo has given the whole team a boost as well as providing a goal threat, raising the work rate of Frenchman Martial - who scored the opener in United's 2-0 win over rivals Manchester City.

"You've had a reaction as well from Martial," he told Sky Sports. "Sometimes a new striker comes in, you praise the new striker, but then that pushes the other lads.

"There's almost been a reaction from Martial, thinking: 'Oh, I've got another player to fight with for my position'. And there's been a good reaction."