Mike Schmid wants Esher to rediscover the mental toughness that has propelled them to the brink of the Championship.
The Molesey Road chief was disappointed with the complacency that marred their 34-24 victory over Tynedale last weekend.
It was Esher’s 10th straight National League One triumph and carved open a six-point lead at the top, with a game in hand on London Scottish.
But Schmid was unhappy with Esher’s second-half display, that allowed the Northumbrians to match the home’s side’s four-try tally and collect a bonus point.
He admitted: “I was disappointed with the effort because we allowed ourselves to drop five or 10 per cent mentally in the second half.
“We got the bonus point for four tries just after half-time and then eased off because we thought we had got everything out of the game.
“Complacency is a dangerous thing and we must make sure we get ourselves right for Blackheath because they are a good side.
“We have got to be mentally tougher and make sure we don’t give hope to sides.”
Esher won on Saturday thanks to tries from Rod Turner, Shawn Renwick, Seb Jewell and Garrick Cowley, while Sam Ulph added 14 points with four conversions and two penalties.
But Schmid was dismayed to see Tynedale dominate physically after half-time and wants to see a big improvement in the London derby at Blackheath.
He added: “We lost the physical battle in the second half and I was certainly not happy with that part of our game.
“I also don’t think any of the players were happy about it, because we expect a lot of ourselves and there were a few bruised egos.
“We beat London Scottish a few weeks ago because we won the physical battle and we must make sure that part of our game is right.
“But the boys are pretty honest with each other and they know they have to improve their work-rate.
“I know we are not going to be at our best every week and at least we still won the game.”
Schmid wants Esher to step back up a gear at Blackheath and is expecting a huge challenge from their London rivals even though they are currently a lowly 10th.
He added: “It’s going to be a very tough game and we must make sure we work as hard as we can.
“They should have beaten London Scottish at home a couple of weeks ago and even though they can be a bit of a Jekyll and Hyde side, I’m sure they will want to beat us badly.
“They have a good pack and are very physical at the breakdown so we know we will have to be at our best.
“We’ve come a long way this season and we have got to make sure we see the job through now with 11 games left.”
Esher hope to have locks James Inglis and Paul Barker available while Harlequins duo Joe Marler and Sam Smith could also return to action after being on England Under-20 duty.
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