He has earned seven in his time so far, first, with Bradford Bulls and now the Headingley club.
However, the ex-England captain will break more records tonight when he faces Warrington Wolves at Old Trafford in, remarkably, his tenth Super League Grand Final.
That takes him one clear of his former Bradford colleague Leon Pryce and long-time St Helens adversary Paul Wellens.
It has been a remarkable odyssey which has helped the tireless and formidable Peacock earn a reputation as one of the sport’s all-time greats.
Speaking exclusively to the Yorkshire Post, here he takes us through his recollections of each of those finals, charting the ups and downs of his amazing affinity with Super League’s biggest show.
2001: Bradford 37 Wigan 6
DC: Your Grand Final debut... with that scoreline you must have thought all this was so easy!?
JP: It was great just to be in my first Grand Final. My overriding memories are two things – firstly, Lesley Vainikolo coming along and celebrating like he had been playing with us all year, when he was really coming in 2002 and hadn’t even played a game for us!
But, secondly, to go in 26-0 up at half-time of a final. I remember being sat in the dressing room and Nobby (Bulls coach Brian Noble) was saying ‘It’s not won this.’ But we were looking around at each other and thinking “Yeah, it is. Yeah, it is.” We went out and won it. A great start.
2002: St Helens 19 Bradford 18
DC: Saints and that Sean Long drop goal...?
JP: Probably my main memory is feeling upset for Brian (McDermott). It was his last-ever game and to lose that way – to a drop goal in the last seconds was obviously upsetting for myself but for Mac as well. You don’t want to finish your last match like that and I can always remember him trying to charge down Longy’s drop kick; that epitomised his whole career – such hard work.
2003: Bradford 25 Wigan 12
DC: 2003 and the year of the treble.
JP: It was just a massive year for myself (Man of Steel etc). I had a bit of a slip-up at the beginning but to do the treble was fantastic.
My lasting memory of that final is Jimmy (Lowes) scoring from dummy-half – it was his last game. You sort of knew he’d get over.
2004: Leeds 16 Bradford 8
DC: Leeds’s first title. Did you think they’d go on and dominate so much?
JP: Probably not as long as they have done. But that was the year of the Rhinos really.
The Bulls had really been usurped by Tony Smith’s Leeds side and though we beat them in the play-off game to get to Old Trafford, they deserved the win on the night.
I just remember Maggsy (Danny McGuire) going in and scoring late on and then realising we weren’t going to win this one.
In all honesty, though, I don’t think it would have been right if we did.
2005: Bradford 15 Leeds 6
DC: History made by winning it from third this time... and your last game for the Bulls.
JP: Just a great journey. And a crazy one. To go from the record defeat against St Helens – 66-4 at home in June – to win every game on the bounce was stunning.
It was especially impressive beating St Helens away to get to the Grand Final and then winning it itself was great.
I really remember the guys and the times afterwards; we celebrated that one pretty hard!
You couldn’t have scripted it any better for anyone to finish at a club; my last action with Bulls was to lift the Super League trophy.
DC: Bulls signed Adrian Morley on loan from Sydney City Roosters for the last six games. Andy Lynch was the unlucky one to miss out on the Grand Final. Is he speaking to Moz yet!?
JP: The coach and board bring in players. It wasn’t Moz’s fault. If Lynchy doesn’t want to speak to him it’s probably Chris Caisley and Brian Noble he needs to speak to!
Moz gave us real impetus, though, going into there and I think maybe if he’d had gone back to Leeds the result might have gone the other way round.
When you add an international player of that quality and calibre it’s only going to help the team.
Ten finals is a great achievement for me but I think what Moz has done is just as good.
To not only play for four different clubs in four Grand Finals but to play in the first one with Leeds in 1998 and, 15 years later, captain Warrington on Saturday is just as big an accolade. To win one in Australia with the Roosters too and be the only Englishman to win a Grand Final in both comps...
2007: Leeds 33 St Helens 6
DC: Your first title with Leeds in Tony Smith’s final game.
JP: We were underdogs to St Helens all year and probably still recovering from bombing in the 2006 season.
But Tony got us prepped and I just remember coming in at half-time and thinking it was close – only a couple of points in it – but knowing we’ve got these. Absolutely got them.
We came out and blew them away in the second half with a terrific performance. It’s great to be out there in a final when there’s 20 minutes left and you know you’ve won. You can enjoy the occasion.
Often when you’ve won a final and you lift the trophy, half the stadium is empty but when it’s full like that you could really savour the atmosphere.
I enjoyed that one as well because I played 80 minutes at prop which was a big personal achievement.
2008: Leeds 24 St Helens 16
DC: Saints again but a lot closer.
JP: This is when they all start to merge into one! Webby was missing and Lee Smith came in. St Helens hammered us in the play-off that year and so we were underdogs again.
All the talk was about how they’d exact revenge and beat us but it just didn’t happen that way.
We had the gameplan and Smithy had a brilliant match at full-back – probably the highlight of his career.
2009: Leeds 18 St Helens 10
DC: Three defeats in a row for Saints and Brian McClennan’s last game.
JP: Those three games, especially the two under Bluey (McClennan) were particularly the same.
They had a similar type of conditions and we ground out the win.
2011: Leeds 32 St Helens 16
DC: More records as you stun everyone from fifth spot.
JP: Looking back now, it’s up there with the Bradford one in 2005. The ‘against all odds’ achievements are the ones everyone likes. Just watching the Ryder Cup last weekend, I think that was extra special because Europe came from so far behind and were massive underdogs going into the last day.
Those Escape to Victory style wins are the best and that was a great feeling 12 months ago.
My abiding memory of that final was when Zak (Hardaker) scored his try. Me and Bedsy (Danny Buderus) were about 50 metres back and we just looked at each other knowing we’ve done it... we’ve won but overcome insurmountable odds to achieve it.