Willstrop senior passed away last year, with James having stepped up since and started coaching alongside his playing.
And his eight-year-old son Logan has got a taste for the coaching, giving his old man tips in his bid to defend his Commonwealth Games title.
It almost was not enough in an epic quarter-final clash with Scotland’s Rory Stewart, Willstrop coming through 11-5 9-11 7-11 11-6 11-8 despite trailing 7-4 in the decider.
And the 38-year-old admits that his son might have to come up with a few more tips after having to dig incredibly deep.
He said: “Logan is interested in his sport and he loves his squash. Not many athletes get to share it with their children. Most kids aren’t interested but he’s interested and we talk about it.
“He sent me an email this morning with his tactics and we share it. It’s been part of the thing all season, I want to get here for him and share it with him but you don’t get this every week. This is miles different to the PSA tour, 1,600 people hardly turn up to a World Championship final. It’s a different world.”
Willstrop was a strong favourite to get the better of Stewart, but had his work cut out against the Scot, who had beaten his protégé Patrick Rooney in the previous round.
The typical fluency was absent, but in what will likely be his final singles appearance at the Commonwealth Games, he gave it everything to ensure there would be two more matches.
He added: “A lot of it was digging in hard. I wasn’t feeling that fluent with things and the short game wasn’t what I wanted.
“I don’t usually celebrate like that. If you’re out, you’re out. At least now it gives me a couple of goes at a medal. I was thinking about that, I don’t know how many more times there will be. I said it last time but there isn’t going to be another singles Commonwealth Games, I don’t think.
“So I was going to give it everything in that fifth, that was the overriding thought, just give everything because I want to be back and play again.”
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