Roberto Martinez's charges overcame the Hammers in an entertaining encounter, with the hosts looking comfortable despite the threat of a late comeback from the newly promoted side
Wigan earned a confident 2-1 victory over West Ham at the DW Stadium courtesy of fine volleys from Ivan Ramis and James McArthur.
The victory was just reward for a strong display from Roberto Martinez's side, whose slick movement and passing was too much for the visitors, with Jean Beausejour, Shaun Maloney and Arouna Kone tormenting the Hammers defence throughout.
The 4,000 travelling fans were left with more questions than answers as a lack of an alternate option in the wake of Ricardo Vaz Te's injury left them looking predictable.
Martinez started Franco Di Santo up on his own, with support coming from Beausejour on the left, while Andy Carroll and Kevin Noble started for the away side, with boss Sam Allardyce looking for his side to go on the offensive from the off.
Both sides started brightly, with the Hammers looking to hassle the Latics defence as early as the first minute - Andy Carroll heading an early chance over before slamming a free kick into the wall minutes later.
Despite the early warning signs coming from the visitors it was Wigan who struck first, and in spectacular fashion. Beausejour won a corner in the eighth minute, and swung the ball into an unmarked Ramis, who blasted in a left-footed volley from 18 yards out. Jaaskelainen was furious with his defenders being nowhere to be found.
West Ham created few chances after a frenetic opening, but James Collins almost turned in an effort on 36 minutes following a Noble free kick, only to struggle to get the ball out of his feet to allow Ali Al Habsi an easy gather.
During a frantic five-minute period Kone and Di Santo wasted three opportunities between them, and Carroll almost found an equaliser in injury time after heading wide from Noble's delivery.
McArthur gave the home side a two-goal advantage two minutes into the restart. Jaaskelainen shanked a clearance to concede possession, and the ball was worked in from the left to free the attacker to slam home a half-volley as the Hammers again failed to pick up their men.
Wigan nullified Carroll's threat by picking up the midfield runners behind him, leaving the forward isolated. Carroll had a golden opportunity on the hour mark but couldn't control a fine cross, with the ball running harmlessly away from danger.