England reined in their natural instincts to reach stumps on day one on 231 for four having been inserted by West Indies in the third Test.
Ben Stokes has been included in England's 12-man squad for the final Test against the West Indies despite a bruised right heel with Keaton Jennings a shock call-up in place of Ben Foakes.
Buttler's first scoring shot was an edge off Shannon Gabriel to which a leaping Shimron Hetmyer at second slip could only get his fingertips.
England's contented mood at the end of the day was in sharp contrast to the situation just three hours earlier as Joe Root's personal tale of batting woe on this disastrous Caribbean campaign continued. Since then, they have lost Test series both at home and away to many teams like India and Bangladesh to be significant and had to play a qualifier tournament to make it into the 2019 ICC World Cup in England and Wales.
"This is still a challenging wicket so to come off (the field) four wickets down, we're pleased with that".
Ben Stokes was dismissed for 79 in St Lucia as Windies wicketkeeper Shane Dowrich took a superb catch on the run.
Root's painstaking innings of 15 off 54 deliveries leaves him with a tally of just 54 runs from five innings, typifying England's desperate struggles with the bat from their first innings of the series when they were routed at Kensington Oval for just 77 on the way to a 381-run mauling. After given life by the no ball, the all-rounder helped England pass 200.
Paul struck again soon after lunch, Rory Burns falling plumb lbw for 29 to a ball that was crashing into the middle of middle - the Windies needing a review to overturn umpire Kumar Dharmasena's not-out call.
Jennings's Test career appeared on hold after he was dropped following the ten-wicket defeat in the first match in Antigua but he is now back with Jonny Bairstow taking the gloves.