Wigan have signed David Thompson for the rest of the season, with a view to a permanent move.And the Latics are also believed to be close to completing the loan signing of Liverpool striker Neil Mellor. Thompson joins from Blackburn, where he has played just eight games this season, after a series of knee problems. Liverpool striker Neil Mellor has not played for the Reds since the FA Cup exit at Burnley last season, and is likely to move to the JJB Stadium for the rest of the campaign. He has had surgery on both knees and made his comeback for Liverpool's reserves last month. Blackburn boss Mark Hughes felt the time was right to let 28-year-old Thompson leave after three years of knee problems. Hughes said: 'It has been difficult for David. He has had a lot of injuries and he was coming to the end of his contract here. 'We have a lot of options in midfield, and it was a case of looking at the balance of the squad and seeing what we need for next year.'