Wigan went down to a narrow 1-0 defeat against Primera Division side Celta Vigo in their final pre-season friendly.
The Latics began the match in the Balaidos Stadium brightly with Albert Crusat forcing a good save from Javi Varras in the home goal, but they came under pressure towards the end of the first half and Alex Lopez was unlucky to see his strike crash against the crossbar.
Vigo continued to press in the second period and Ali Al Habsi was forced into several fine saves before Iago Aspas finally found space at the far post to beat the Wigan goalkeeper for the game's only goal.
Blackburn Rovers finished off their pre-season preparations with a 3-1 win over Cork City.
Steve Kean's men had to come from behind to beat the Irish side, with new signing Colin Kazim-Richards netting twice for Rovers.
Blackburn fell behind after just six minutes when Andy O'Connell scored from close range after Paul Robinson failed to hold Kalen Spillane's shot.
The Championship side drew level 10 minutes later when Kazim-Richards volleyed home Bradley Orr's cross and the Turkish international gave Rovers the lead six minutes into the second half with his second of the contest.
Rovers added a third on the hour mark when Morten Gamst Pedersen's curled home a fine free-kick to set up Blackburn for next week's Championship opener with Ipswich.