The extraordinary thing about Alisson Becker’s winning header for Liverpool on Sunday was that West Bromwich Albion should have known what was coming. There was, after all, a recent precedent - three weeks ago, St Johnstone goalkeeper Zander Clark also came up for a corner in the dying seconds of extra-time in a Scottish Cup tie against Rangers, heading goalwards before Chris Kane turned it over the line. It earned a 1-1 draw before St Johnstone won on penalties (Clark saving two in the shoot-out, just for good measure). In terms of technique Clark’s header was nowhere near as good as Alisson’s. But there are parallels, not least because no defender attempts to mark him. Or rather, a bit like the West Brom players with Alisson, they just do not know what to do. Despite being the big bloke with the bright shirt on, he stands on his own. So is this a trend? Probably not. The two examples are freakish outliers and there are countless other instances where goalkeepers have ambled up-field and then ambled back without having come remotely close to scoring. But maybe the tactic should be given far more serious consideration, and not simply considered a last, desperate roll of the dice. After all, research has claimed that a third of all goals are scored directly or indirectly from set-plays. Every club has someone who works on their corner and free-kick routines and, ironically, that person is often the goalkeeping coach. So why are managers so reluctant to use a tactic which allows them to get an extra player - and one who is generally among the tallest in the side - into the penalty area? As long as they leave a defender as quick as Andrew Robertson to cover a breakaway – as Liverpool did – is there really that great a risk? And if a forward counter-attacks and is one-on-one with the goalkeeper the chances are he will score anyway. No, the main reason for not doing it is because coaches are worried about being left embarrassed as the opposition walk the ball into an empty net while his goalkeeper is marooned up the pitch.