The WBA striker's club-mates, Keith Andrews and Simon Cox, featured positively for the Irish against Czech Republic, who provided a glimpse of what to expect in Poland
The visitors played with five in midfield and with Ireland due to face Croatia, Spain and Italy in Group C, it is a system that Long says the Irish side will have to deal with at the Euros.
“They’re a good side and have a few big players in their team," he said. "They were going to be a good test for us. I know they play with five in midfield and we need to be able to play against that with the teams we have in our group.
“It was a good learning curve for us before we go to the Euros,” the West Brom striker told reporters after the game.
The match finished level after a late Simox Cox goal cancelled out Milan Baros’ 50th minute opener. The equaliser had a WBA feel to it as Long’s team-mate Keith Andrews won the initial ball for fellow Baggie Cox to finish past Petr Cech.
“Obviously, I play with the two of them at West Brom. Keith broke down the ball well and put Simon through, a good first touch put him in on goal and he finished it from a tight angle.
“It’s a great finish. Obviously, he’s done well since he’s come into the squad and I’m delighted for him."
The loudest cheer of the evening was reserved for the introduction of Sunderland’s James McClean, making his Republic debut as a late substitute for Aiden McGeady.
The 22-year-old made a couple of runs and had a shot from distance blocked in a generally positive cameo run-out. Long, winning his 24th cap, says that McClean’s emergence has now given Giovanni Trapattoni a selection problem.
The former Reading player said: “Obviously, he’s flying at Sunderland at the moment. He’s pledged allegiance to Ireland and that means a lot to the Irish fans and it’s nice to give him that confidence. Hopefully he continues the way he’s playing for the rest of the season.
“He’s a top quality player. I’ve seen it with my own eyes this week in training. James can deliver a ball from anywhere so when he gets it, you make a run and he’ll find you.
“It’s a different option on the wing and it’s a problem now for the manager going to the Euros.”