Arsenal kept their hopes of winning a famous double on track with a fiery 2-2 draw in the first leg of their Europa League last-16 tie at Sporting CP on Thursday.
The Gunners took the lead, went behind and fought back to ensure it ended all square at Estadio Jose Alvalade in a four-goal encounter high on drama.
First-half headers from William Saliba and Goncalo Inacio left the two sides on level terms at the break, before Paulinho's tap-in had pushed Ruben Amorim's men in front.
But a Hidemasa Morita own goal just beyond the hour mark ensured Mikel Arteta's Premier League leaders will head into next week's second leg level with the Portuguese side.
On a humid evening, both teams started in cagey fashion, creating few clear-cut chances amid an atmosphere of simmering tension.
That taut mood increased in the 22nd minute when Saliba rose to power Fabio Vieira's corner home, with an off-the-ball altercation involving Oleksandr Zinchenko then sparking a minor melee.
Sporting refused to be cowed by their concession though, and took just a dozen minutes to strike back in near-identical fashion, with Inacio the man to divert a Marcus Edwards set-piece past Matt Turner.
The hosts then hit the front just 10 minutes after the restart, when Turner parried a Pote attempt straight to Paulinho, who fired home from close range.
Arsenal rose to the occasion once again though, albeit not without controversy after Bukayo Saka was adjudged to have been committed a foul in the build-up to Granit Xhaka's finish ricocheting in off Morita.
That left the tie nicely poised ahead of the return leg at Emirates Stadium next week.