Celtic boss Neil Lennon has refused to name his transfer targets but confirmed he is looking to strengthen his team.
Fulham's Aaron Hughes insists Dimitar Berbatov must remain at Craven Cottage if they are to avoid relegation.
The 20-year-old former Wigan trainee is yet to make a first-team appearance for the Latics but he is currently first choice at Northampton in League Two, where he is on loan.
Wigan boss Roberto Martinez told www.wiganlatics.co.uk: "Seeing Lee's progress from a young age has been a joy and to have him stay here and continue his hard work is great news.
"Lee is a great goalkeeper and he has shown that at Northampton this season. He has had some outstanding performances and we are really looking forward to continuing to work with him."