The Blues were 1-0 winners against the Dutch side at the Amsterdam Arena last month thanks to Michy Batshuayi’s 86th-minute winner.
Tammy Abraham scored a second-minute own goal to give Ajax the lead before Jorginho levelled from the penalty spot two minutes later.
Ajax surged into a 3-1 lead before half-time thanks to Quincy Promes’ strike before Hakim Ziyech’s free-kick was deflected into the net by Kepa Arrizabalaga’s face.
Chelsea FC appeared to be out of the content when Donny van de Beek made it 4-1 in the 55th minute.
However, Cesar Azpilicueta got on the scoresheet in the 63rd minute to start a crazy 11-minute period in the Champions League clash.
Daley Blind fouled Abraham in the initial sequence before Joel Veltman handled the ball in the area as the referee allowed Chelsea FC to play on following the initial tackle.
Jorginho scored from the penalty spot to make it 4-3 as Blind and Veltman were both sent off in the 73rd minute.
A minute later, Reece James levelled the Champions League tie before Azpilicueta’s winner was ruled out for handball.
Speaking to BT Sport after the eight-game thriller, Lampard opened up about his team talk at half-time of the Champions League clash.
“The two own goals were the story of our first half. We were in the first half,” Lampard said.
“I said to the lads at half-time – I’m not trying to say how clever I am – but I said, ‘I think we’re going to draw this at least 3-3, could be 4-4, could be 4-3 and we could win it. It’s up to us.’
“Because if we got rid of those crazy moments that gave them the goals – some misfortune, some on us – I just felt we were so in the game.
“We were just short of that last pass in the final third, Christian Pulisic looked so dangerous, Willian looked dangerous and I just thought we’d build momentum and fortunately we did.”
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