Across his two spells as Northern Ireland boss, Michael O'Neill has been blessed with no shortage of centre-back talent.
Jonny Evans, Aaron Hughes, Gareth McAuley and Craig Cathcart were mainstays of his first stint in charge - so much so that, in some of the biggest games of O'Neill's managerial career at Euro 2016, the quartet all started across a flat back-four.
Since returning to the job four years ago, O'Neill has switched to three at the back, with Sunderland duo Trai Hume and Dan Ballard providing an injection of Premier League quality in what remains a side largely drawn from the Championship and League One.
But with Hume, something of a Swiss army knife in the squad, covering the injured Conor Bradley on the right flank and even starting in centre midfield against Ukraine last month, and Ballard presently nursing an injured hamstring, change has been required through this Nations League campaign.
Despite those forced alterations in defence, the side go into their concluding Group B2 fixtures against Ukraine and Hungary top of their pool and the only side at any level of the competition yet to concede a goal.
At the heart of their defensive efforts have been Ruairi McConville and Tom Atcheson, two young centre-backs already described by their international manager as having "no ceiling".
