#4 John Stones and Micheal Keane (England)

A pairing whose time might come sooner than any other on the least, Stones and Keane are certainly the go-to pair for the Three Lions in the future.
With both players having recently made big money moves to upper crust Premier League clubs, Stones is looking comfortable as the defensive lynchpin of a very good Manchester City side after an uncomfortable first season.
Keane, after excelling at Burnley, made a big-money move to Everton and while the initial results and performances have been average at best, his long-term England place is not in doubt.
Like the best centre-back pairings, the Stones-Keane double act is expected to marry skill and technique (Stones) to brawn and grit (Keane). There have already been calls for the pairing to be the first choice at the World Cup and with the competition; Gary Cahill, Phil Jones, Chris Smalling, and co. failing to pull up any trees, the pair might find themselves starting at the World Cup.
One of the more experienced pairings on this list, the two have earned 24 caps between them with Stones (20) and Keane (4).