Arsenal took the lead against Sporting CP in the 22nd minute of their Europa League clash through defender William Saliba.
The French international headed home from a corner to break the deadlock in Lisbon following a superb Fabio Vieira delivery. However, the away side barely had time to celebrate before a number of Sporting players were seen squaring up to Gunners left-back Oleksandr Zinchenko.
Whilst the corner was swung in, Zinchenko appeared to hold one of Sporting's players before they both went to ground - something that the Portuguese outfit felt should have led to the goal being disallowed. The finish was allowed to stand but both Zinchenko and Sporting defender Sebastian Coates received yellow cards following the brief coming together, with Coates now suspended for the return leg in north London next week.
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The home side then scored from a corner of their own just 12 minutes later, with January signing Jakub Kiwior appearing to duck whilst goalkeeper Matt Turner decided not to try and claim the cross, allowing Goncalo Inacio to score the equaliser. Mikel Arteta's side will be hoping to take control of the game in the second half, with the likes of Emile Smith Rowe, Thomas Partey and Takehiro Tomiyasu on the substitutes' bench.
The second leg will then be played at next Thursday at the Emirates Stadium.
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