Arsenal fans fumed when Bruno Guimaraes signed for Newcastle in January after being linked with the north London club.
Guimaraes had been a long-time target for Arsenal, but Eddie Howe pulled off a major coup by signing the Brazilian for £33m while Mikel Arteta and Co dragged their heels.
The midfielder did his best to rub salt in the wounds, posting a video on social media that appeared to mock their interest by showing newspaper cuttings linking him with Arsenal, before cutting to a montage of Newcastle's history and himself posing in the club's shirt.
One scorned fan took to Twitter to say Newcastle would get relegated, while another accused the Brazilian of declaring war on Arsenal supporters.
Imagine how foolish they must be feeling now, after Guimaraes' late goal at St James' Park condemned Arsenal to a 2-0 defeat and all but ended their hopes of playing Champions League football next season.
Everything went through the Brazilian. He had the most successful passes (40), most touches (73), and most possession wins (8) as Newcastle thoroughly outplayed a side that sat seven places above them.
It was a typical display for the man at the heart of the Magpies' revival this season.
Newcastle were in the relegation zone with just two wins to their name all season when Guimaraes made his debut from the bench in a 3-1 victory over Everton.
He was initially eased into the side by Howe, but since starting for the first time against Southampton at St Mary's, where he got on the scoresheet with an incredible backheel, his form has helped drag the side up to 12th.
They are even within touching distance of a top half finish ahead of their final game of the season away at Burnley on Sunday.
After being eased into Premier League football with his first five appearances coming from the bench, Guimaraes has notched the best goal involvement per minute rate at Newcastle, with six goals and assists in 943 minutes.
The man he's overtaken, Allan Saint-Maximin, had been the difference-maker for Newcastle, a spark when they were struggling.
Guimaraes offers something altogether more promising, a glimpse of a team that can compete for trophies.
When Saint-Maximin was sprawled on the ground clutching his shin against Manchester City, it was Guimaraes who pulled him up to carry on playing. Newcastle lost the game 5-0, but the attitude from the 24-year-old was telling.
There is hope as well that Guimaraes' presence at Newcastle, and his clear affection for the club, may attract similar stars to Tyneside.
Speaking to the Newcastle Matchday Programme, Guimaraes said he would love to see his Brazil and former Lyon team-mate Lucas Paqueta join him on Tyneside, calling him 'a family member that football has given me', as reported by Newcastle World.
Paqueta has scored nine goals in 36 games this season and been a key member of a Lyon side that sits eighth in Ligue 1.
With Newcastle's combination of newfound wealth and a charismatic midfielder that big players want to play with, more could choose to follow the Brazilian's example.
