Goals from Sam Lavelle, Connor Mahoney, Luke Wall and a brace from Dean Rittenberg saw the young Rovers continue their winning pre-season sequence.
Rovers started confidently with three first half goals. Lavelle opening the scoring for Eric Kinder's side, following up a half-cleared corner to smash the ball into the top corner from 15-yards.
The second goal was one to savour as Mahoney beat a host of Annan players down the right before cutting inside and finishing superbly into the far corner.
A third soon followed with Rittenberg grabbing his first of the night, turning well on the edge of the box to rifle the ball home.
Rovers continued to impress in the second half with the midfield trio of Hyuga Tanner, Bradley Bauress and trialist Sean McIntosh dictating play. A fourth goal soon followed as Rittenberg converted from the spot after the impressive Mahoney had been brought down.
As the match approached 90 minutes a fifth and final goal came Rovers way, Luke Wall taking advantage of a misunderstanding between defender and goalkeeper to fire home.
Speaking after the match, coach Eric Kinder was delighted with the team display: "With illness and injury we went up there with a really young squad. It was a big ask but we responded magnificently with a very good performance.
"We scored five good goals and it could have been more against a side that reached the League Two play-offs last season. Our football was exceptional at times.
"The lads looked like they enjoyed playing football for each other, they ran themselves into the ground and got their rewards. Their challenge now is to carry that on."
ROVERS: Kean, Carson, Doyle, Tanner, Lavelle, Daly, Wall, McIntosh, Rittenberg, Bauress, Mahoney.
Subs: Paulo Jorge, Cham, Crump.