A defeat to Aberdeen in the fifth round at Celtic Park ended his hopes of retaining the trophy. So the Hoops boss will have to settle for watching former team-mate McNamara and his long-time friend Wright slug it out.
Lennon is perfectly placed to judge the two sides - Celtic beating Dundee United 3-1 at the weekend just four days after being held to a 3-3 draw by St Johnstone.
But he admits picking a winner is beyond him, and acknowledged: "It's very close to call. You have a little contrast in styles. Jackie's players like to play football. Tommy's team are powerful, keep going and have ability in their ranks."
You get the feeling Lennon reckons there could be one final upset in this year's competition.
"There is an idea going into the game that it's the purists against the hard-working team.
"But I don't see it that way. There is plenty of ability in the St Johnstone team."
Who handles their nerves best could have a major advantage, and Celtic Park will be bouncing.
Lennon believes that augers well for the game in this country and said: "It just shows you, when there is success, people will come and support their local team.
"It's great St Johnstone are in the final, and it's great experience for the younger players at Dundee United.
"How they handle the occasion is another thing.
"St Johnstone, by beating Aberdeen, showed they've got over that psychological hurdle of getting to the final.
"They've both had very good seasons, and I'm very close to both managers - so I hope it's 6-6."
Lennon has always been impressed by McNamara's knowledge of the game, and is not surprised at how successful he has been since moving into management.
Wright is a fellow Northern Irishman, whom he has known for decades.
Lennon said: "They both like to win. Jackie's a quieter type, but he takes everything in. Despite their looks, they're both pretty intelligent.
"How the teams set up will be interesting, in particular, how Tommy tries to stop their midfield from getting a grip of the game.
"Dundee United are going to have a real problem handling May. Stevie has had a very good season. St Johnstone will do well to hold on to him, but they are quite confident they can."
Whichever manager comes out on top, it will be a massive boost to his CV.
Despite the fact that, this week, Danny Lennon and Gary Locke lost their jobs, Lennon reckons there is no shortage of talent among the managerial ranks in this country.
"Up here, you get the opportunity to play and coach in a top league," insisted the man who has now been in charge of Celtic for more than four years.
"You get a little bit more exposure than you probably would elsewhere and you get the opportunity to win things as well. That's good for your own mentality and the way you like to set teams up.
"Scotland has done fantastically well over the years with managers.
"There's just a hunger about the Scottish boys. Maybe they're harder than some of the English lads.
"They've got a good mentality about the game, and this is a very good breeding ground for that."