Steve Harper played in both of those most recent successes - and is hoping Rafa Benítez's side can claim another rare win in Hertfordshire on Saturday.
The former goalkeeper, who spent 20 years on Tyneside between 1993 and 2013, was back at St. James' Park this week ahead of the world premiere of Bobby Robson: More Than A Manager - the definitive film about Sir Bobby’s incredible life and career - which will be held at the stadium on 22nd May.
And Saturday's game brought back memories of a Carling Cup penalty shoot-out success over the Hornets in November 2006. Antoine Sibierski had given United an early lead but Damien Francis forced extra time before Danny Shittu looked to have won the game for the home side in the 108th minute.
But Scott Parker took the game to penalties and there, Harper proved to be the hero as he saved from Jordan Stewart after Ashley Young had already missed from 12 yards to send Newcastle through to the quarter-finals.
"That still remains the only competitive shoot-out we've ever won," Harper told nufc.co.uk more than 11 years on.
"I remember winning there in the Championship a few years after that (Fabricio Coloccini and Andy Carroll were on target in a 2-1 win in February 2010), but that was a special night. I didn't save many penalties so it's quite ironic that I've got the record as the only (Newcastle goalkeeper) ever to win a competitive shoot-out!
"It was a good night under Glenn Roeder. Tim (Krul) was training on the pitch before the game that night and hurt his knee; Pav (Srnicek), back at the club, was on the bench that night."
Looking ahead to the weekend, Harper believes Newcastle are capable of returning to winning ways after two successive losses, but warned: "It's a difficult place to go.
"I think they did alright in stages against Tottenham (on Monday evening) and had a couple of good spells.
"And on Saturday against West Brom, we just dropped our levels and played against a team still desperate for a result and got caught out a little. But we’ve got a top drawer manager and I'm sure he won’t let that happen again."
A small number of tickets for the world premiere of Bobby Robson: More Than A Manager, which will see the film screened on the pitch at St. James' Park, are still on sale - more details are available here
