Lincoln City climbed back into the play-off places following a blood-and-thunder goalless draw with promotion-chasing Wycombe at Sincil Bank.A near sell-out crowd gave former Imp Gareth Ainsworth a rapturous welcome on his return to the cathedral city and he will have been the happier of the two bosses as he saw his side consolidate third spot with a hard-earned point.Following a niggly opening, Chairboys keeper Scott Brown tipped Matt Green's effort onto his crossbar and over the bar, as a corner caused panic in the visitors' box.Wycombe responded, with Adebayo Akinfenwa heading Sam Saunders' cross over, before City keeper Ryan Allsop kept out a fierce effort from Matt Bloomfield.Allsop then produced a terrific stop from his own defender Scott Wharton as his under-pressure clearance flew towards his own goal.Matt Rhead headed home Sam Habergham's cross on the stroke of half-time only for referee John Brooks to harshly rule it out for a foul by the Imps striker.Lee Frecklington then crashed a shot narrowly over the bar in first half injury-time when slipped in by Green.A well-worked free-kick inside two minutes of the second half saw Green fire Habergham's pass just over, before Allsop at the other end dived low to his left to keep out Michael Harriman's shot.Allsop then saved well from Nathan Tyson, before the veteran frontman was again somehow denied by the Imps' sprawling custodian.