Scott McTominay's Napoli Serie A title rivals show they're up for fight after all-time dramatic classic

Internazionale claimed their place in the Champions League final in one of the most memorable ties of the competition's history after overcoming Barcelona 4-3 after extra time at the San Siro.

There were wild celebrations in Milan at full time as the Nerazzurri maintained their hopes of achieving a historic double - with veteran defender Francesco Acerbi an unlikely goalscorer to thwart Barcelona in the semi-finals right at the death of normal time.

Inter will now face either PSG or Arsenal in the final on May 31 and gave the rest of their season a huge shot in the arm as they look to reel in leaders Napoli in Serie A with just three matches remaining.

Francesco Acerbi scored in stoppage time to keep Inter alive against Barcelona. | Getty Images

Simone Inzaghi's side trail Napoli - who have been inspired by Scotland talisman Scott McTominay in recent weeks - by three points and have a tricky encounter away at Torino on Sunday evening, while Napoli are at home to Genoa a couple of hours later.

Full focus will now be on domestic matters, with the prospect of a spareggio - a one-off play-off should the teams finish level at the summit - if Antonio Conte's men are caught. Napoli have the easier run in on paper with games against Parma (a) and Cagliari (h) to end the campaign, while Inter have Lazio (h) and Como (a). While fatigue will likely be high after this match on the continent, they showed that they are up for title fight with their battling credentials against Barca.

The first leg in Barcelona was a thrilling affair that finished 3-3 and there were doubts that the drama and action in Catalonia could be matched back at the San Siro. The two teams made a mockery of such thoughts with an incredible encounter in northern Italy.

High drama in Milan

Inter raced into a two-goal lead on the night and 5-3 on aggregate by half time. Argentinian striker Lautaro Martinez opened the scoring on 21 minutes before Turkish forward Hakan Calhanoglu converted from the penalty spot in stoppage time after a foul on Martinez.

Barcelona refused to be floored by those goals and roared back in an extraordinary second half. Eric Garcia halved the arrears on 54 minutes and on the hour mark, Dani Olmo made it all square with a close range header.

Yann Sommer makes a big save from Lamine Yamal late on. | Getty Images

The visitors thought they’d won it on 88 minutes when Raphinha scored but into added-on time, Acerbi netted a rare goal with a neat finish from Denzel Dumfries’ cross to send the San Siro wild and force extra time.

Inter took the momentum of that late leveller into extra time and nosed themselves in front on 99 minutes when Davide Frattesi belted into the far corner after good work from Marcus Thuram.

Barca, propelled by teenage sensation Lamine Yamal, pushed for a goal, but Inter keeper Yan Sommer made two excellent saves to deny him and Inter will head to Munich at the end of the month.