Tom Lawrence saved Town with a late equaliser in a rip-roaring FA Cup tie at Portman Road.
Lincoln looked to be heading into the fourth round when Theo Robinson put his side ahead again just past the hour with a terrific volley.
Lawrence conjured up his fifth goal of the season though five minutes from time with a drive from distance escaping Paul Farman in the Lincoln goal.
Robinson had given the Imps an early lead before Lawrence struck back immediately with a solo run from deep finished with a right foot strike.
Lincoln had the better chances and it needed a brilliant tackle from Josh Emmanuel to save the day for Blues in added on time, leaving a repay on Tuesday week.
Mick McCarthy named five youngsters on the bench, with David McGoldrick and Leon Best joining seven other players on the injury list as Town’s resources were stretched to the limit.
The game began in the worst possible way for Blues on eight minutes, Nathan Arnold found room on the right and from his cross Robinson planted the ball past Dean Gerken from close range to send the 5000 Lincoln fans into full voice.
Town responded immediately, Lawrence dancing past four Imps before his shot found the net through the legs of ‘keeper Farman.
Luke Waterfall did well to head Grant Ward’s pass that was destined for Freddie Sears back to his ‘keeper, Sears then getting in down the left but his cross was cleared by Sean Raggett, Arnold then denied at the other end by Jonas Knudsen as he made progress down the right.
Brett Pitman’s long ranger was well over the bar as the game settled down after a frantic start, Gerken saving comfortably from Arnold.
Adam Webster had to be alert to clear from Robinson six yards out after Matt Rhead headed on from a free-kick, Christophe Berra then in the right place to stop Robinson getting in from another right wing cross.
Alan Power’s effort was deflected wide as Lincoln pressed for the advantage, then at the other end Andre Dozzell was inches away with a left foot effort after a driving run from Josh Emmanuel.
Pitman’s overhead kick was dealt with by Farman, Emmanuel then doing well again to get down the right but his cross was too high for Sears at the far post as the half came to an end with the tie up for grabs.
Knudsen blocked Arnold’s cross after the Danish international had initially lost possession, Sears and Kevin Bru linking up well to create space for Knudsen as Town responded, his cross hacked clear.
Arnold almost found Robinson with a cross as the Imps responded, former Derby striker Robinson then crowded out as he looked to twist away from Berra inside the box.
It needed Gerken’s alertness to deny Arnold as the Imps dangerman burst in on goal, the winger far more off target with a speculative volley from 25 yards.
Rhead’s header was plucked from under his bar by Gerken, then Sears spun and smashed a left footer just wide.
Gerken held firm from Sam Habergham’s curler from the edge of the box but the goal that had threatened to come did on 64 minutes, Robinson volleying in superbly after Town failed to deal with a long ball.
Lawrence fizzed a 30 yard free-kick over the bar as Town searched for an equaliser, Pitman firing over after Ward had set him up.
Robinson made way for Jack Muldoon for the last 10 minutes in the game’s first change, Farman doing well to divert Dozzell’s header to safety.
Town found an equaliser five minutes from time and it was Lawrence who again provided it, his 25 yard drive finding the bottom corner.
Lawrence threatened seconds later, Farman forcing his effort behind, then Emmanuel did superbly to get back and save Town as Alex Woodyard went clear on goal to take the tie back to Sincil Bank on January 17.
Town: Gerken, Emmanuel, Webster, Berra, Knudsen, Ward, Lawrence, Dozzell, Bru, Sears, Pitman. Subs not used: Bialkowski, Fowler, Webber, Douglas, McDonnell, McLoughlin, Morris.
Lincoln: Farman, Wood, Habergham, Waterfall, Power, Rhead (Long 90), Hawkridge, Raggett, Arnold, Woodyard, Robinson (Muldoon 81). Subs not used: Walker, Marriott, Miles, Fixter, McCombe. Booked: Robinson.
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