City were beaten at home as two quickfire second-half goals saw Swansea City come from behind to take all three points.
Reeco Hackett’s penalty gave the Imps a deserved lead at the break, but goals from Moussa Yeo and Stephen Eustáquio shortly after the restart turned the game around.
The Imps created the first opportunity after two minutes when a long throw from Andrei CoubiÈ™ fell to Hackett, whose effort was punched away by Swansea goalkeeper Lawrence Vigouroux.
A City free-kick caused further problems for the visitors four minutes later, with the delivery dropping into a dangerous area before Swansea managed to clear.
The Imps threatened again after 18 minutes when a clever pass found Freddie Draper, who sent his effort narrowly wide.
City continued to put pressure on the visitors and earned a corner after Vigouroux was penalised for holding onto the ball for too long. The resulting delivery skimmed through a crowded penalty area before a Swansea defender cleared the danger.
Draper then looked to capitalise on another mistake from Vigouroux after 22 minutes. The goalkeeper lost possession under pressure from Ben House, but recovered in time to gather the resulting effort.
City’s pressure was rewarded when Draper was brought down inside the area after 38 minutes and the referee pointed to the spot.
Hackett stepped up two minutes later and emphatically fired his penalty into the top corner to put the Imps ahead.
Swansea looked for a response during first-half stoppage time, but Sonny Bradley produced an important block to help ensure City went into the break with their advantage intact.
The visitors levelled three minutes after the restart. A move down the right resulted in the ball finding Yeo, who finished into the bottom corner beyond George Wickens.
Swansea completed the turnaround just two minutes later when Eustáquio found a route through a crowded area and into the net.
City looked for a response and went close after 58 minutes when Deji Elerewe played the ball towards Hackett, whose clever backheel went narrowly wide.
The visitors made a triple change a minute later as Ronald, Joseph Opoku and Zan Vipotnik replaced Yeo, Elijah Just and Adam Idah.
City responded with three substitutions of their own after 64 minutes, with Chiedozie Ogbene, Yunus Konak and Mikkel Ladefoged replacing Adam Reach, Conor McGrandles and House.
Ladefoged made an immediate impact, with his first touch producing a clever pass inside the area before Swansea managed to clear the danger.
Another long throw from CoubiÈ™ caused problems after 70 minutes. Tom Bayliss saw his initial effort blocked before the ball fell to Draper on the edge of the area, whose cross was headed clear.
Bayliss went close himself two minutes later when he received possession just outside the box and fired narrowly wide.
Both sides made further changes after 77 minutes, with Gonçalo Franco replacing Eustáquio for Swansea and Rob Street coming on for Ryley Towler for the Imps.
Swansea made their final substitution four minutes later as Jensen Seelt replaced Stephen Welsh.
City continued to push for an equaliser and three consecutive long throws kept Swansea under pressure after 82 minutes. The third was met by Konak, who headed the ball back into the penalty area before the visitors cleared.
The Imps had another opportunity in stoppage time when a free-kick from outside the area drifted narrowly wide.
Coubiș launched one final long throw into the box after 93 minutes, but Vigouroux gathered the ball to bring City’s hopes of finding a late equaliser to an end.
Imps: Wickens, Reach (Ogbene 64’), Coubiș, Towler (Street 77’), Hackett, Bayliss, McGrandles (Konak 64’), Bradley, House (Ladefoged 64’), Elerewe, Draper.
Subs not used: Gauci, Jefferies, Varfolomeev, Wheatley, Oyegoke.
Swansea: Vigouroux, Cabango, Stamenic, Widell, Just (Opoku 59’), Tymon, Welsh (Seelt 81’), Lissah, Idah (Vipotnik 59’), Eustáquio (Franco 77’), Yeo (Ronald 59’).
Subs not used: Fisher, Fulton, Iorpenda, Parente.
Attendance: 10,559 (1,201 away)
