Joe Hart believes it's time for Javier Hernandez to establish himself as the main man at West Ham.

Hernandez, who joined the Hammers from Bayer Leverkusen this week, has previous experience in the Premier League, having scored 59 goals in his five-year stint with Manchester United.

The 29-year old was primarily used as an impact player for United and found it hard to establish himself as a starter in a dominant team.

But Hart believes Hernandez must show his worth as a top striker in the Premier League.

"He's a finisher. Sir Alex Ferguson over the years was a genius at having players like that and using them at the right time in pursuit of winning titles," Hart said told Sky Sports.

"He probably felt he should have had more game time, but you have to balance that with some of the players that United have had over the years.

"He went to Real Madrid and then Leverkusen, still scoring goals in the Champions League and still showing what a top player he is.

"Now is his time to come back to the Premier League and show he should be a No 1 striker."