THREE red cards midway through the second half marred a feisty local derby in National League Two South, writes Chris Wilson.
But Hartpury's superior finishing prowess and defensive solidity saw them consign Lydney to their tenth consecutive defeat
The sendings off came with the visitors leading 25-9 and having survived ten minutes of Lydney pressure in their 22.
Play was five metres from the Lydney line when a maul erupted.
After consultation with the touch judge, the referee dismissed Lydney's Jim McMahon and Andy Jarrett along with Hartpury's Harry Casson for their parts in the disturbance.
With a man advantage, Hartpury were able to pick Lydney off on the counter and added three more tries, although they did concede a score to the tireless Dave Bennett towards the end.
Coach Duncan Bell would have been pleased with Lydney as patient play kept Hartpury in their own 22 and Tony Wicks kicked two long range penalty goals to give them an early six-point lead.
Hartpury were beginning to show they were capable of the killing thrust and with Sean Marsden linking well and Alex O'Meara looking sharp they soon reduced the deficit.
A kick to the corner from Luke Cozens found O'Meara unmarked for a simple dot down for the game's opening try with 13 minutes gone.
The second was not long in coming. Wicks was ruled to have obstructed Steff Reynolds as he chased his kick forward and from the penalty lineout catch and drive Callum O'Connell scored.
Ben Lewis was sin-binned for contesting the decision and following Cozens' successful conversion, Hartpury were awarded a penalty on halfway.
Despite being a man down, Wicks' third penalty cut the deficit to three points but Hartpury grabbed a try just before the break as Wicks' attempted downfield kick was swallowed by Seb Rodwell's midriff and he made the 40 metres to the line.
The visitors were able to counter with pace in the second half and a superb charge down the wing from Brandon Walker gave Reynolds the chance to race in at the corner.
Lydney set up camp in the Hartpury 22 but found themselves suffocated by a defence that had conceded only 11 points per game on their travels. Even with Darren Crompton in the sin-bin, there was no way through for the Severnsiders.
Lydney found themselves under pressure and Cozens chipped over a penalty goal after his interception and break won the decision under the home posts.
Then came the flurry of red cards and the visitors made the most of their advantage.
From the penalty, Hartpury's powerful pack drove the home side over their line and O'Connell scored his second try, converted by Cozens.
Marsden then scored in the corner after Tim Stevenson linked well with Reynolds and Cozens added a fine goal.
Lydney broke through with five minutes to go when Bennett broke two tackles to score, Wicks adding the conversion.
Following the score, the home side finally found some belief but being shorthanded, they were open to Hartpury's pace on the counter and Reynolds sped over for his second try, again courtesy of Stevenson's break and good hands from Cozens who converted with the last kick of the game.
LYDNEY: T Wicks; M Goodall, C Holder, D Chui, A Hall; C Russell, M Williams; A Ledner, B Lewis, S Winchcombe; J Connors, D Bennett; M Taylor (Capt.),T Longton; J McMahon. Reps: A Jarrett (for Winchcombe, 59), M Gore (for Goodall, 69), J Thorne (for Taylor, 67), C Farrell (not used), J Fields (for McMahon, 19-27; for Lewis, 56).
HARTPURY: S Marsden; A O'Meara, J Hayes, S Rodwell, S Reynolds; L Cozens, C Stuart-Smith; J Gibbons; C O'Connell, D Crompton, B Walker (Capt.), H Casson, G Mills, L Wilkinson, N Thomas. Reps: R Cano, (for Wilkinson, 53), D Rodrigues (for O'Connell, 69), S Pitchford (for Thomas, 69), T Stevenson (for Hayes, 24), B Field (not used), W (for Gibbons, 63), Gibbons (for Cano 69 bb).
Referee: Tom Foley (RFU Appointment)
Star Man: Tony Wicks (Lydney) was solid at full back while Brandon Walker was superb for Hartpury lurking out wide