Anthony Crolla was frustrated by the judges as his WBA world lightweight title fight against Darleys Perez was ruled a draw.
Stablemate Scott Quigg retained his WBO world super bantamweight title with a blistering second-round stoppage of Spain's Kiko Martinez.
Crolla appeared to have clinched a belt of his own in a close fight which saw Perez twice docked points for frequent low blows — but the judges were split, with one ruling for each fighter and the third calling it a draw.
Crolla was cheered into the ring by a crowd who sang his name to the rafters throughout, and his beaming smile told the story.
He landed a couple of useful early left hands in a largely cagey opening round, Perez responding with a quick four-punch combination late in that round and a good uppercut early in the second.
Crolla rocked the Colombian with a right hook, but Perez settled and perhaps regained the upper hand over rounds three and four.
Perez was warned for a low blow in the sixth and Crolla landed a combination shortly afterwards, though Perez’s counter-punches continued to be dangerous.
Crolla too was warned by referee Howard Foster in round eight before Perez received a lengthy talking-to in the 10th, Foster repeatedly telling him: "No more."
The message did not get through and Perez was docked a point in round 11 and another in the next, seemingly putting Crolla’s success beyond doubt.
But the judges had other ideas, with the three cards showing a 114-113 win for Perez, 116-111 to Crolla and finally a 113-113 draw.
“I thought I’d done enough to be world champion,” Crolla told Sky Sports 1 before pitching for a rematch.
“Darleys Perez is a great fighter, I’m sure the Manchester crowd would want to see him back here and we’ll go again.
“I proved tonight I can mix it at world level, and I’m only going to get better. I’ll go out and win a world title here in Manchester, I promise you.”
Asked about the points deductions, he added: “I thought that had done enough, I did get hit low throughout the fight.”
Promoter Eddie Hearn said: "I felt he'd won the fight, even without the deductions. With the two-point deductions, I don't see how you can't give that fight to Anthony Crolla.
“The good news is Anthony Crolla proved he’s world class. He should be a world champion and we’ll get him another shot.”
Crolla was embraced ringside by Quigg, who had no such worries as he produced a statement performance against former IBF world champion Martinez.
His win sparked calls for a match with the current holder of that belt, Belfast's Carl Frampton, who beat Alejandro Gonzalez Jr in Texas.
Martinez began the fight on the front foot but Quigg came roaring back in the second round, flooring his opponent almost immediately with a superb uppercut.
The fight continued but Quigg sensed he had his man in trouble and waded in with a barrage off both wings.
A vicious right hook sent Martinez to the canvas for the second time in a minute and though the Spaniard attempted to scramble to his feet, referee Terry O’Connor shook his head and stopped the fight with little hesitation.
Quigg told Sky Sports 1: “The second round he came out with a bit more oomph and that just set him up for the shot.
“I got him with the punch we’ve been working on all through camp, it was a peach of an uppercut.
“After that I looked across at Joe (Gallagher, trainer) and just went out to finish it. I probably looked a bit wild, but I was trying to stay as calm as possible.”
Hearn added: “I’m just pleased Scott Quigg finally gets the respect he deserves. His stock’s going to keep on rising and obviously the Carl Frampton fight’s the one everyone wants.”