Mesut Ozil and Alexis Sanchez in training ahead of Saturday lunchtime’s crunch clash

Gunners fans receive welcome boost as superstars prove their fitness for trip to face old rivals at Old Trafford

ALEXIS SANCHEZ and Mesut Ozil gave Arsenal boss Arsene Wenger a huge boost ahead of the crunch clash with Manchester United.

The superstars – back from international duty – proved their fitness for tomorrow’s lunchtime kick-off in training today.

Sanchez flew to South America for Chile duty but text Wenger to let him know he was fit and raring to go despite the gruelling trip.

And in a week where they lost Hector Bellerin to injury, Gunners fans will be delighted to see the speedster in action alongside terrace favourite Ozil.

Olivier Giroud will likely be used off the bench again if Sanchez is fully fit, with the Frenchman struggling for game time this season.

Jose Mourinho took the opportunity to aim yet another jibe at Wenger in his pre-match press conference, commenting on his rivals lack of recent success.

But the Frenchman refused to play ball and let the Special One do all the talking.

The latest young talent off the Arsenal production line, Joe Willock, trained with the first team today.

The 17-year-old is described as “a stylish midfielder with a good passing range, Joe is also a powerful runner and, like his brother, has a few tricks up his sleeve” on the Gunners’ website.

Opponents United have been plagued by injury problems all season, with Eric Bailly and Antonio Valencia currently on the sidelines.

England defenders Luke Shaw and Chris Smalling were criticised by manager Jose Mourinho for telling him they weren’t fit enough to play in the Swansea victory and both could be left out as a result.