The goalkeeper will be part of the AFC Portchester squad that travels to Corsham Town on Saturday - one of 208 ties taking place in the extra preliminary qualifying round.
Back in 2012/13, Mowthorpe was in the Blackfield & Langley team that reached the fourth qualifying round. That season’s Wessex League champions were just 90 minutes away from the chance of drawing Portsmouth - but lost 2-0 at Hastings.
In the third qualifying round that season, Mowthorpe had helped Blackfield shock higher tier Sholing 3-1 in Southampton.
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Fast forward to 2017/18 and Mowthorpe was at Moneyfields when Dave Carter’s men reached the third qualifying round for the first time. Again, it was a Sussex club that ended the run - Worthing winning 3-2 at Dover Road.
Mowthorpe’s crowning FA Cup glory run, though, came at Chichester City in 2019/20.
They became the first club to progress from the extra preliminary round to the first round proper - winning six ties - for 70 years.
Then, amazingly, they were given a bye through to the second round - the space vacated by Bury being kicked out of the EFL for financial reasons.
Drawn away to Tranmere Rovers, Mowthorpe kept a first-half clean sheet against a team five tiers higher in the pyramid - before the hosts’ class told and they ran out 5-1 winners.
‘Football moves on pretty quickly, but that’s going to be a memory that stays with me forever,’ he told The News.
During that run, Chichester thrashed the little known Bridon Ropes - based in Charlton, south east London - 7-2 away, but also dumped out three higher division clubs in Hartley Wintney (after a replay), Enfield Town and Bowers & Pitsea.
A 2-1 win on Bowers’ 4G pitch took Chichester, from the eighth tier of the pyramid, into the first round proper – the first time the club had reached that stage since 1960 (when they collapsed to an 11-0 loss against Bristol City).
‘Winning at Bowers & Pitsea was my most memorable day of that cup run,’ Mowthorpe remembered. ‘Then you’re in the first round - territory you’d never thought you’d get into.
‘What was our secret? I’m not too sure I could tell you - we worked hard, we had a real belief, and we had a major part of all cup runs - we got lucky.
‘In terms of the actual draws, I don’t think we played any team that was too many places above us. We were always confident we could get a result.’
The summer signing of former Pompey star Brett Pitman is just one of the reasons Portchester have been installed by many non-league followers as Wessex title favourites this season.
The Royals will also privately fancy themselves for a decent run in the FA Vase. And if they reach the third qualifying round of the FA Cup, then Mowthorpe will have been part of another club record run.
Of course, that’s easier said than done. Corsham, from the Premier Division of the Hellenic League, play at the same step 5 as the Royals. And the winners have to go to Southern League Sholing - for Mowthorpe, a potential repeat of Blackfield’s famous success a decade ago.
‘This is an exciting place to be,’ said Mowthorpe. ‘The club is set up to go up. What goes on behind the scenes is unbelievable. It’s just up to us to do it on the pitch.
‘Almost every player has played in at least the league above, there’s definite quality. Hopefully we can put that into practice.
‘Portchester were the favourites last season, and probably the season before that. We can’t let it get into our heads.
‘It would be nice to help the club out financially (via a good FA Cup run) if we do well, and it would give us a bit of recognition. There’s a reason why it’s the greatest domestic competition in the world.’
Portchester have reached the second qualifying round stage on four occasions, the last time in 2017/18 when they lost 2-0 at Truro.
Mowthorpe kept his first clean sheet of 2022/23 on Tuesday when a Brett Pitman header gave them victory over Cowes in their Wessex Premier curtain-raiser.