Another player coached by Cheika at Leinster, full-back Rob Kearney, is set to make his first appearance of the tour off the bench after recovering from a grade one hamstring tear.
The Irish link continues with the presence of Alan Gaffney in the Waratahs coaching set-up. 'Riff' coached at Munster and Leinster in the recent past and was Ireland's backs coach when they won the Grand Slam in 2009.
Cheika enjoyed Heineken Cup and Celtic League success during his time in Dublin, and was pleased to see six Leinster players make the Lions cut - five of whom he gave provincial debuts to, including prop Cian Healy who has since departed the tour with an ankle injury.
"I'm a bit disappointed they all played on Tuesday because I would have liked to get a shot on a few of them," admitted Cheika, with reference to the fact that Brian O'Driscoll, Sean O'Brien and Heaslip played in midweek against the Combined NSW-QLD Country side.
"Not me personally but I have a few players in the team who could. Those lads would know that's the way and that's what I would have liked them to do when I was coaching them."
Speaking ahead of the Lions team announcement, he added: "That would have been a great opportunity for us to clash. It would have felt a bit weird for me but there's still a chance some of them might play.
"We're playing against a team with massive artillery so if we start looking down the barrel of one or two players it's only going to lead to disappointment. So I'd say, just anything in red that moves, we'll have a crack at."
Sexton has recovered from the tight hamstring he suffered last Saturday against the Queensland Reds and will make his second start of the tour, pairing up with Wales' Mike Phillips at half-back.
The Dubliner's development into a world class out-half has pleased the man who backed him to deliver in the knockout stages of the 2009 Heineken Cup.
Sexton famously replaced the injured Felipe Contepomi in the semi-final victory over Munster, kicking seven points in the 25-6 success at Croke Park, and he accumulated 11 points - including a classy drop goal - when Leinster overcame Leicester Tigers at Murrayfield to be crowned European champions for the first time.
Cheika agreed: "Johnny's going very well, just the confidence in the player and the way he's setting up the play and carrying the ball in both hands and keeping the opposition on the back foot.
"I just think he's really matured into an excellent footballer. He deserves it because he's a competitive bugger and he wants to fight his way to the top, even when he's at the top. I think you'll see the best come out of him on this tour."
With just over a week to go until the first Test against the Wallabies, Sexton will be keen to nail down the number 10 jersey by orchestrating the Lions' fifth successive tour win in Sydney.
His Leinster and Ireland colleague O'Driscoll sits out the Waratahs match having captained the Lions in their 64-0 hammering of Combined Country. His three tries in two starts suggest the veteran centre can be just as influential in the Test series as he was during the 2001 tour to Australia.
Cheika speaks with pride of his time with Leinster and the early input he had in the careers of the likes of Sexton and Heaslip, while his admiration of an evergreen O'Driscoll has clearly not diminished.
"I was involved, not responsible, in the development of these players and having faith in the system. And that experience in Leinster is really helping me in what we're doing here in New South Wales," he explained.
"I learned a lot from that experience in how to bring a team round and implement a winning attitude and maybe bring back some old-school values in rugby that in the sanitary professionalism world have sometimes got lost.
"I think at Leinster they've got a perfect balance of that. You've only got to look at the way O'Driscoll has been playing on this tour to see what type of team they are because they're the leaders.
"He's still at his best and he's what, 50 now? Is he 51 or 52? He's still as strong as an ox, he's been brilliant."
Meanwhile, the chances of the Waratahs giving the Lions a difficult night at Allianz Stadium have increased with the release of four players from the Wallabies and Australian Sevens camps.
Waratahs captain Dave Dennis and centre Rob Horne have been given the green light by Robbie Deans to link up with Cheika's squad for the game, while half-backs Bernard Foley and Matt Lucas, who were in the midst of a Rugby World Cup Sevens training camp, are also now available to play.
It is a welcome boost for Cheika who had been forced to call up eight Shute Shield players to cover the absence of the club's 10 Wallabies, six injured players and two on Sevens duty.
Benn Robinson, Sekope Kepu, Kane Douglas, Michael Hooper, Wycliff Palu, Berrick Barnes, Adam Ashley-Cooper and Israel Folau remain with Deans' Wallabies this week, while the Waratahs' injured contingent includes Tatafu Polota Nau (broken arm), Greg Peterson (dislocated shoulder), Mitchell Chapman (medial ligament), Sitaleki Timani (broken thumb), Michael Hodge (torn hamstring) and Lachie Turner (broken leg).
"We're going to have a strategy to go out there and play the game a certain way. Queensland went out there with their strategy and I don't think we can play like that, so we're going to have a different strategy to play our game.
"We certainly won't be going out there to look for a glorious defeat. We'll be doing our best and like I said to the lads, if there's a 1% chance of us winning the game, we've got to take that 1% and do what we can with it," concluded Cheika.