* Arsenal beat West Ham 3-1 at Emirates stadium
* Arnautovic gave West Ham a 25th-minute lead
* Monreal equalised on the half-hour mark
* A second-half Diop own goal fired Arsenal ahead
* Substitute Welbeck sealed the win in stoppage time
* West Ham host Wolves next, Arsenal visit Cardiff
Aug 25 (Reuters) - Arsenal celebrated their first Premier League win of the season under new manager Unai Emery after coming from behind to beat London rivals West Ham United 3-1 in an action-packed match on Saturday.
A Nacho Monreal strike, Issa Diop’s own goal and Danny Welbeck’s stoppage-time effort enbaled the Gunners to bounce back from their opening two defeats after Marko Arnautovic had fired West Ham into a 25th-minute lead.
Monreal equalised five minutes later, drilling a fierce shot from eight metres past two defenders on the line after goalkeeper Lukasz Fabianski parried Hector Bellerin’s cross into the defender’s path.
Arsenal took the lead when Diop’s poor clearance resulted in Alexandre Lazazette’s cut-back cannoning off the defender’s body into the net and Welbeck sealed the win after Bellerin’s cross gave him time and space to beat Fabianski from close range. (Reporting by Zoran Milosavljevic; Editing by Ed Osmond)