Manchester United hero Paul McGrath has called into question Lisandro Martinez's height after defeat at Brentford.

Lisandro was hooked at halftime of United's 4-0 defeat in London.

McGrath wrote for the Sunday World: "Now before you jump at me and say men like Fabio Cannavaro and Franco Baresi were brilliant, but small, centre-halves. I know they were, but they played in Serie A, where teams didn't throw in lots of crosses.

"After last night, half the Premier League is going to be licking its chops at the idea of sending their biggest centre-forward up against 5ft 9ins Lisandro Martinez.

"He was a brilliant defender for Ajax in recent season.

"But again, in Dutch football, there's no great emphasis on using the forehead of a 6ft 3ins centre-forward.

"There certainly is in English football and Martinez has so much to learn – and quickly."