England, at stumps on the fourth day of the third Test, were 221 for five -- a deficit of 205 runs and still needing a further 56 to avoid the follow-on -- with Ian Bell 76 not out.
A West Indies' 10th-wicket Test record stand of 143 -- the third highest in all Tests for the last wicket -- of 143 between wicket-keeper Denesh Ramdin, who made 107 not out, and Best took the tourists to 426 all out.
Fast bowler Best's innings was all the more impressive as this was his first Test in nearly three years, with his previous highest score at this level 27.
The Bajan then took two wickets for 37 runs in 12 overs to set the seal on a memorable day.
There was no hint of the run-fest to come when West Indies, resuming on 280 for eight after losing the toss, saw Ravi Rampaul dismissed three balls into Sunday's play.
Ramdin, himself in Test exile for two years before this tour, was then 63 not out.
But Best made England pay for their controversial decision to rest new-ball duo James Anderson and Stuart Broad, having already established an unassailable 2-0 lead in this three-match series.
'Stand-in' seamers Graham Onions and Steven Finn were driven in the style of a top-order batsman by the 30-year-old Best.
Indeed it was Ramdin who was almost out when, on 69, he cut Finn and Kevin Pietersen failed to hold a sharp chance at gully.
Off-spinner Graeme Swann went the same way as the pacemen, cut for two fours in successive balls by the inspired Best.
There was no stopping Best, only called up to this tour as a replacement for injured fast bowler Shannon Gabriel, as he completed a 44 ball-fifty.
Ramdin's single off Tim Bresnan, after which he nearly hit the bowler's head as he waved his bat in celebration, took him to a hundred in 160 balls with nine boundaries.
Ramdin, who made 166 against England at Bridgetown three years ago, then produced a piece of paper from his pocket with "Yea Viv, talk nah" written on it, after West Indies great Vivian Richards had criticised him for failing to deliver on his promise after the tourists' nine-wicket second Test loss.
England were too often 'chasing' the game, with captain Andrew Strauss slow to reinforce his ring of close catchers.
Best uppercut Bresnan for yet another boundary to top Zaheer Khan's previous Test best by a No 11 of 75 for India against Bangladesh at Dhaka in 2004 and then drove the seamer for a stunning straight six.
But in sight of a hundred, Best skyed an Onions slower-ball to Strauss at first slip.
Best faced just 112 balls with a six and 14 fours.
His partnership with Ramdin erased the previous West Indies 10th wicket Test record of 106 put on by Carl Hooper and Courtney Walsh against Pakistan at St John's in 1993.
After Alastair Cook and Jonathan Trott fell cheaply, the 30-year-old Best's day got better when he had Strauss brilliantly caught by first slip Darren Bravo to leave England 49 for three.
Bell, on 20, survived a sharp chance to short leg Adrian Barath off debutant 'mystery' spinner Sunil Narine.
But otherwise Narine, who'd produced remarkable figures in his brief first-class and Indian Premier League career, posed few problems with Pietersen driving him for a huge six over long-on.
However, Pietersen exited for 78 when he guided spinner Marlon Samuels to West Indies captain Marlon Samuels at slip.
England were now 186 for four after Pietersen and Bell had put on 137 and there was still time for Best to bowl Jonathan Bairstow as the batsman aimed across the line.
