It's been a massive rebuild for Ange Postecoglou at Celtic following a disastrous campaign last term.
However, with just two transfer windows he has revamped the squad and taken them to the brink of the Scottish Premiership title.
With the Scottish Cup semi-final against Rangers around the corner and the Premier Sports Cup trophy already in the Parkhead cabinet, a shock Treble is a real possibility this season.
It doesn't feel that long ago that Rangers consigned Celtic to their first trophyless season in over a decade with a Scottish Cup fourth round win in April 2021.
But when you look at the team from that day it almost feels as if it is from an alternative timeline.
Only Callum McGregor started the 2-0 defeat at Ibrox on April 21, and the 2-1 victory for Celtic on Sunday.
Bain was given the nod ahead of Vasilis Barkas and Conor Hazard as Neil Lennon searched for his number one goalkeeper midway through the campaign, but is now warming the bench in place of Joe Hart.
Loanee duo Diego Laxalt and Jonjoe Kenny took up the full-back positions, but Greg Taylor and Josip Juranovic have made the positions on the flanks their own in the new system with Postecoglou's patented inverted full-backs.
Everton defender Kenny won't look back on the afternoon in Govan fondly having netted an own goal.
The partnership of Kris Ajer and Stephen Welsh has been replaced by the resolute defensive duo to Cameron Carter-Vickers and Carl Starfelt to complete the backline.
Scott Brown anchored the midfield three, with Ryan Christie and current captain McGregor given the nod by Lennon.
Southampton loanee Moi Elyounoussi and David Turnbull were placed in attacking midfield roles, while Odsonne Edouard led the line.
Edouard would miss from the spot to cap off a lacklustre final season at Parkhead.
Celtic team vs Rangers April 2021: Bain, Kenny, Laxalt, Ajer, Welsh, McGregor, Brown, Christie, Turnbull, Elyounoussi, Edouard.
Celtic team vs Rangers April 2022 : Hart, Taylor, Juranovic, Carter-Vickers, Starfelt, McGregor, Hatate, Rogic, Maeda, Giakoumakis, Jota.