Eddie Howe hopes Bruno Guimaraes was not bidding Newcastle a fond farewell after scoring the goal which clinched seventh place.
Guimaraes capped a 4-2 win at Brentford with a late strike and celebrated in front of the away fans in a Toon bucket hat.
The Brazil midfielder, linked with a move away this summer, then spent a long time waving to the travelling support after the final whistle.
“I don’t think it’s a wave goodbye,” said Magpies boss Howe. “I think Bruno probably does that many times.
“But I think it can be interpreted in a way if people watching decide that to be the case.
“Certainly from my side, I hope it’s not. He’s integral to what we are doing. He’s an inspirational player and we are desperate to keep him.”
A wild afternoon saw Newcastle sweep into a 3-0 lead at half-time through goals from Harvey Barnes, Jacob Murphy and Alexander Isak.
Vitaly Janelt and Yoane Wissa hauled Brentford back into the match before Magpies favourite Guimaraes settled it when he tucked in the rebound from Isak’s free-kick.
It was a goal which means that if Manchester City win the FA Cup final next weekend, Newcastle will be back in Europe in the Europa Conference League.
“I think it’s been a season of progression even if the league position tells me different,” said Howe. “I couldn’t be happier with where we are. But that has to continue.”
Howe was without winger Anthony Gordon due to an ankle injury which will also keep him out of the club’s post-season tour to Australia and potentially make him a doubt for England’s Euro 2024 squad.
“He had a scan after the Manchester United game,” added Howe.
“I don’t think it’s serious, but it was enough to keep him out of today and Australia.”
Brentford, for their part, finished 16th in their third season in the Premier League.
“I think it’s a successful season – how do we define success is always a good question – but for me success is every year we are in the Premier League with our size and our budget,” said boss Thomas Frank.
“We are creating small miracles because over a long time we have a top structure and culture, and have been out-performing bigger clubs.
“I want more, we want more, to improve and develop and I am an optimistic guy. I can only dream of what could have been achieved with a more normal injury record. I’m excited for the future.”
Ivan Toney, whose goal drought stretched to 12 matches, is widely expected to leave Brentford this summer.
But Frank insisted: “I’d like to keep him. I know there’s a lot of rumours but for now Ivan is a Brentford player.”