Kieran Tierney and Alexandre Lacazette both participated in Arsenal on Tuesday.
Both players had been expected to miss Thursday's crunch Europa League semi-final leg against Villarreal.
The Gunners are down 2-1 heading into the meeting into north London.
Speaking after the 2-0 win over Newcastle United on Sunday, Mikel Arteta said of the duo: “They haven't trained with us yet so it is very unlikely to have them ready in the next few games."
However, things have seemingly improved for Tierney and Lacazette as they returned to training on Tuesday.
Afternoon, lads
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— Arsenal (@Arsenal) May 4, 2021