"It hasn't sunk in. There have been a lot of great fullbacks over the last 100 years,'' said Slater notching his milestone with a typically breathtaking effort in the 71st minute on Saturday.
He raced after a Cameron Smith kick and grabbed it with one hand from the clutches of Jordan Rankin before somehow grounding the ball a whisker before hitting the dead-ball line.
At 28, and looking quicker than ever, if that's possible, Slater could set a mark which may never been broken, especially if he joins a select few players whose careers have reached the 300-game milestone.
There was a time, though, when a young Slater, who's won every accolade in the game, dreamt of winning a jockey's premiership, not rugby league ones.
Back then he was throwing a leg over finely-tuned thoroughbreds weighing more than 500kg at track work, experiencing quite a different adrenalin rush.
Had he been able to drop his weight, his passion for horses could have seen him riding in Golden Slippers and Melbourne Cups.
Fortunately for rugby league, he was too heavy to be a jockey.
"The choice was taken away from me because I was about 70kg when I was riding work for Gai when I was 16,'' recalled Slater after claiming Wesser's record.
"It would have been hard to drop 15 or 20 kilos as a 16-year-old.
"It's still a passion of mine. I love the horses and I love the racing side of things.
"Maybe one day I might to train a few horses and experience the thrill of winning a few races.
"But football has always been No.1 for me. I grew up playing rugby league; I've been playing it since I was four years old.
"I still get a thrill being out there playing with my mates.''
With six tries already this season, Slater has scored half his 2011 season haul in just three games.
"He's a freak, an absolute freak, the best I've ever seen,'' said former Penrith premiership-winning forward and Titans coach John Cartwright after Saturday's loss.
Melbourne coach Craig Bellamy, instrumental in bringing Slater from Brisbane Norths to the Storm, said he was proud of their star player.
"To be the greatest tryscoring fullback in rugby league history is a pretty big wrap for him,'' said Bellamy.
"Langlands was my favourite player as a kid. I didn't see Churchill but I saw Langlands, Graham Eadie, Garry Jack, Gary Belcher and I don't think I've seen a better fullback.
"No I haven't.''
