The England defender was named in the starting line-up for the clash, but was notably not named as captain with the armband going to Tom Heaton instead.
It was a big statement from Erik ten Hag after stripping of the captaincy at the end of last term, giving it to Bruno Fernandes on a permanent basis.
Unfortunately Maguire failed to cover himself in glory upon his return to the team, gifting Bilbao a first half goal at the AVIVA Stadium in Dublin.
Giving the ball away in his own half, the Spanish side broke free and made it 1-0 in front of the Stretford End.
That resulted in unsavoury scenes as supporters in attendance started to boo Maguire every time he touched the ball.
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However he made up for that by cushioning a header for Facundo Pellistri to drill home to end the game 1-1, but many will be more inclined to focus on his first half error than his second half redemption.
While the England defender will have thick enough skin to deal with the criticism, it will only fuel speculation about his future at the club.
West Ham United have been linked with a move for Maguire this summer, reportedly making a £20million offer for the 30-year-old.
However talkSPORT understands that Ten Hag would like the defender to stay at the club with their relationship amicable.