Both sides went close before Knoyle settled the contest just shy of the hour mark with his first goal of the season and second in 77 games.
Right-back Knoyle, who played in a back three in Tom Anderson's absence due to illness, leathered the ball home from the edge of the box following Ben Close's cutback.
The win halted Rovers' two-game losing streak in League Two and moved them up to tenth and within two points of the play-offs.
13. George Miller - 7
Led the line selflessly but should have scored when played through one-on-one by Adam Clayton in the second half. Photo: Howard Roe/AHPIX LTD
14. Jon Taylor - 6
Another bench cameo. Made a great run at one stage when he beat three players to help Rovers gain territory high up the pitch. Photo: Liam Ford/AHPIX LTD
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