Whether in 35 years' time Berahino will be found in the press box at Old Trafford commentating on the Baggies for local radio is open to debate.
But the fact such attention was on Tony Brown, the last man to win a game for West Brom at England's biggest club stadium, underlined the magnitude of 20-year-old Berahino's achievement.
"I wasn't fazed by it," said Berahino.
"I have had a bit of experience playing on the big stage because I played at the Under-20s World Cup for England.
"I had been to Old Trafford before, for a reserve game, although I didn't play, so I was desperate to get on.
"It is a great stadium. If you don't want to play here you might as well not be a footballer."
Introduced as Scott Sinclair's replacement early in the contest, Berahino came close to scoring in the first half, then snatched at a chance in the second before the winner came, from a superb lay-off by Morgan Amalfitano, who scored the visitors' opener before Wayne Rooney levelled.
It continued a remarkable few weeks for the Burundi-born youngster, who scored a hat-trick on his debut against Newport in the League Cup last month and also received his first call-ups for the England Under-21 outfit.
And then there was Rio's shirt.
"He just gave it to me," said Berahino. "I thank him for that.
"I can't believe how the last month has gone.
"But the gaffer believed in me. I don't want the journey to end now, I just want to carry on for many years to come."
It was easier for Liam Ridgewell to understand the true significance of West Brom's win.
For while Berahino was experiencing the euphoria of victory on his first trip at senior level, Ridgewell had never previously picked up a point at Old Trafford after 12 years as a professional with Aston Villa, Birmingham and now West Brom.
"The big one was beating Arsenal at Wembley (for Birmingham in the 2011 League Cup final) but this is definitely up there," said the 29-year-old.
"I've never won a point here before. So it was brilliant."
Manager Steve Clarke was anxious to ensure his side reserved praise for their deserved success rather than the focus merely being trained on United's present frailties.
But it is hard to escape the sense of shock at such a terrible start.
"You think about playing Manchester United first of all," said Ridgewell, insisting the absence of Sir Alex Ferguson alone does not fuel additional belief.
"What have you got to lose? I'm sure they will be back to winning ways soon and everyone will forget about this.
"But (David) Moyes is adjusting and it is obviously something you can play on. They will find their feet though -let's see who they play next week."
Modern-day football is a fickle business though.
After all, Clarke guided West Brom to their best league finish since 1981 last term.
Yet, after collecting just two points from the opening four games this time around, some were wondering whether the Scot was still the right man for the job.
"It's crazy," Ridgewell said.
"A couple of results go against us and people suddenly forget how well he did last season."