The England Under-21 international has struggled for fitness of late due to an ankle ligament problem, but he featured for the full 90 minutes in the Foxes' reserves game earlier in the week. As a result boss Nigel Pearson will almost certainly pitch him into the side against the Latics this weekend.
Patrick Kisnorbo also featured in the second string's 2-1 win against West Brom and could line up in defence alongside Mattock in the League One game after a six-month absence due to a knee injury.
Pearson could also be tempted to throw striker Barry Hayles into the side following his successful recent loan stint at Cheltenham in which he bagged three goals in seven games given that Paul Dickov is out with a back problem. Midfielder Stephen Clemence is also still sidelined with an ankle injury.