In the heats Beamish was happy to sit towards the back of the field during a slow first half of the race.
As the race came to the boil the former Collegiate student unleashed his trademark turn of pace to quickly move into contention before powerfully accelerating from sixth with a lap-and-a-half to go through to second at the bell.
For the final 200m he looked in control as he crossed the line second in 7:51.71 to bank one of the four automatic spots for the final.
As a measure of the quality of the opposition, he finished only 0.29 behind the heat two winner Barega and he also took the scalp of Spain's Adel Mechaal – the 2020 Tokyo Olympic 1500m fifth placer – who had to settle for fourth.
Happy to get the job done, Beamish was also delighted at the chance to compete against such a stellar field.
"I thought it would be cool to run against Barega, the Olympic (10,000m) champion," he said.
"I've never really raced anyone of that calibre and I just saw it as a good opportunity. It was fun running the last couple of laps next to him – it was like I belonged in that kind of field.
"Once I hit that last 800m, the idea was to keep an eye on the guys in the top four. I made a move with maybe 300m to go, I made one move and made it stick."
Putting on the Black Singlet for the first time was special, Beamish said.
"After five or six years living in the States it is all starting to feel pretty real."