Theo Walcott is battling to be fit for Arsenal's FA Cup clash with Manchester United.

The England Under-21 winger, 18, is having round-the-clock treatment on a thigh strain. Walcott's woe is another headache for boss Arsene Wenger in the run-up to a crucial week for the Gunners.

First, they travel to Old Trafford for the FA Cup fifth-round cruncher. Then comes Wednesday's Champions League last-16 first-leg clash at home to AC Milan.