England 416 and 348 for 6 (Brook 109, Root 81*, Duckett 76, Pope 51) lead West Indies 457 (Hodge 120, Da Silva 82*, Athanaze 82, Woakes 4-84) by 307 runs
Two strikes late in the morning session by Jayden Seales and another on the last ball before lunch to Kevin Sinclair lifted West Indies from a position where the match looked to be slipping beyond their reach. England added 100 runs to their overnight score but lost three wickets for 19 runs in 7.2 overs.
With four wickets still in hand and Root looking in fine touch, England were still in control and much of that was down to him and Brook, who united for a 198-run stand for the fourth wicket after Ollie Pope and Ben Duckett had fallen in quick succession on the third day, themselves having each passed fifty and put on 119 runs together.
During the fourth morning, Brook and Root looked entirely unflustered and they amassed 52 runs in the first hour to take England to the 300-mark in their second innings, a lead of 259.
Shortly after yet another ball change in this match, Brook brought up his fifth Test ton – and first on home soil – nudging the new one, delivered by Alzarri Joseph, for a single to mid-on. Two balls later, Root clipped one to the leg side to bring up his fifty, and the 150 partnership.
Brook fell a good while after the first drinks break, wafting at a Seales delivery that moved away slightly off the seam, found the edge and sailed through to Joshua Da Silva behind the stumps.
Seales struck again when he removed Ben Stokes cheaply, Stokes turning a short ball straight to Alzarri Joseph at backward square leg.
That brought Jamie Smith to the crease and he managed only 6 before Sinclair drew a faint edge with a delivery on off stump and Da Silva snapped up the catch.