Harry Redknapp is unsure whether England coach Roy Hodgson knows his favoured formation ahead of their first Euro 2016 game against Russia on Saturday.
England have played 4-4-2 with a diamond midfield in their warm-up friendlies, but could be set to revert to the 4-2-3-1 or 4-3-3 used during the qualifying.
Redknapp thinks Hodgson will use a four-man midfield against Russia in Marseille, but would like to see Dele Alli playing in a more advanced role behind Harry Kane and Wayne Rooney.
"I'm not sure Roy knows his best formation," he told Betsafe.
"We've chopped and changed [too much]. I think he'll go diamond - it's how he plays with that system now.
"Harry Kane is the best striker in the Premier League, bar none. He's a fantastic player - he's got to play.
"I can see him taking the gamble and playing [Jamie] Vardy up there - it's just where he plays Dele Alli really. He's got to play as well, somewhere.
"I can see Kane up there playing with Dele Alli and Rooney. It's a good system playing in pockets in between, gives them problems for everybody."
England will face Wales and Slovakia in their subsequent two matches in Group B, but Redknapp believes it could have been worse.
"It's tough, but there are a lot tougher groups than the one we got," he said.
"You look at what Northern Ireland drew out [Germany, Ukraine and Poland]. I don't think we've got a bad group."