The current Saints winger presented the former fly half with a special edition '100' shirt, which had also been signed by the entire squad.
Richard Augustus "Peter" Palmer, OBE debuted for the Saints back in 1930, some 24 years after his father Harry Claude captained the Saints. During his time at the club Peter scored 13 tries in 38 appearances and also represented the East Midlands alongside the likes of Saints legends Ray Longland and Harry Weston.
Born just down the road in Church Brampton, Peter is a proud Northamptonian, much like Diggin who was all too happy to make the presentation and hear some of Peter's memories from his playing days.
"For anyone to reach 100 is a fantastic achievement. I'm only just 27 and I feel like I'm catching him up pretty quickly!" he said. "It's nice that the Saints are still able to recognise the club's history and it's also great to meet Peter, who's played with so many legends of the club."
Peter remains a supporter of the club and still watches every televised game, though he will certainly be forgiven for missing the Saints' semi-final win over the Scarlets last Sunday to celebrate hitting his century.
Happy birthday Peter - hopefully the Saints can deliver a late present this weekend by winning the LV= Cup!