Soares has played 18 times this campaign, with the majority of those opportunites coming in the Europa League, where Arsenal remain unbeaten.
The former Southampton defender spent an extended spell on the sidelines following his arrival, but his move was made permanent at the end of last season.
Speaking towards the end of the last campaign, Arsenal manager Mikel Arteta hinted that Soares offered something completely different to the other full-back options at his disposal.
“He’s a different quality in the full-back area than what we have,” Arteta said. “He’s a gifted, technical player and is probably the best we have in the final third to make the right decision and attack the box as well.
“He can play in a four or a five, he’s a really good player with experience in the Premier League that can help us.”