Clucas scored twice as Swansea City moved out of the Premier League relegation zone with a 3-1 victory over Arsenal at the Liberty Stadium on Tuesday.
Bottom of the table prior to kick-off - Carlos Carvalhal's Swans followed up their 1-0 triumph over Liverpool by beating another heavyweight on home soil, with the result lifting them up to 17th.
Pierre-Emerick Aubameyang's potential arrival has dominated the conversation around the Gunners recently, but Arsene Wenger now has another on-pitch aberration to digest.
Arsenal even took the lead thanks to Nacho Monreal's fourth league goal of the season, only to concede an equaliser just a minute later when Clucas coolly converted a one-on-one opportunity.
A shocking error from Petr Cech, who scuffed a clearance straight to scorer Jordan Ayew, gifted Swansea the chance to go ahead just after the hour mark.
Despite utilising both Henrikh Mkhitaryan and Olivier Giroud off the bench, the Frenchman perhaps playing for Arsenal for the last time as Chelsea reportedly plot a late bid, the visitors' fate was sealed when Clucas slammed home a loose ball in the 86th minute, meaning the travel-sick Gunners have now picked up just 13 points on the road this season.