The Gunners have endured a terrible start to 2018 so far to heap pressure on under-fire Arsenal manager Arsene Wenger.
The north London side lost 3-0 to Manchester City in the League Cup final in an underwhelming performance at the home of English football.
Arsenal went on to lose to Manchester City and Brighton in their subsequent Premier League games to heap even more pressure on Wenger.
With a top-four finish looking increasingly unlikely, Arsenal made the trip to AC Milan in the first leg of their Europa League last-16 clash.
Goals from Henrikh Mkhitaryan and Aaron Ramsey secured a 2-0 win to give Arsenal hope of winning Europe’s second tier competition and booking a place in the Champions League next term.
But former Arsenal midfielder Parlour isn’t underestimating the threat posed by Watford ahead of their Premier League meeting at The Emirates on Sunday afternoon.
“It is a big game,” Parlour told Sky Sports. “You never know what Watford side will turn up.
“They are a physical side. I am sure they will play the same as Brighton. Get the ball into the box and make it difficult.”
Arsenal will welcome Gennaro Gattuso’s Milan side to the Emirates Stadium in the return leg of their Europa League clash on Thursday night.
The Gunners have never won a major European trophy under Wenger.
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