The Devils were trailing by only four points after eight heats, but the Rockets pulled a further six points ahead in the next two races.
Rain started falling heavily during heat 10 to bring a halt to proceedings and the result will stand because the minimum requirement of 10 heats was completed.
Jack Holder top scored for Plymouth with nine (paid 10) points from four rides while Michael Palm Toft, guesting for injured skipper Kyle Newman, had a couple of wins in his seven (paid eight) from four starts.
The Devils operated rider replacement for Todd Kurtz, who was also ruled out through injury, and collected six (paid seven) from three replacement outings.
Next up for the Devils will be the League Cup decider against Somerset at the St Boniface Arena on Thursday evening.
Rye House: Edward Kennett 9 (3 rides), Peter Karger 1 (3), Cameron Heeps 8 (3), Leigh Lanham 4+2 (3), Stuart Robson 2 (2), Reserves: Kasper Lykke 5+2 (3), Ben Morley 6+1 (3)
Plymouth: Brady Kurtz 3 (2), Michael Palm Toft 7+1 (4), Sam Simota 3 (3), rider replacement for Todd Kurtz, Jack Holder 9+1 (4). Reserves: Stefan Nielsen 3 (4), Ellis Perks 0 (3).