But come stumps, England were 235 for six after an unbroken century stand by their seventh-wicket duo.
But at least Buttler, who finished on 66 not out, and Bess (55 not out) justified their selections and gave their team a bit of confidence ahead of a potentially even more hard five-test series against top-ranked India.
Babar was taken to a hospital for a scan which confirmed he would not be able to get back on the field at Lord's or indeed take part in next week's second Test at Headingley.
The hosts soon found themselves in further trouble as Alastair Cook was dismissed for just one.
Before this match he was averaging under 25 in Tests, and is yet to score a hundred, making the injury, coming as it did when he was playing so well, all the more ill-timed.
Alastair Cook, who top-scored with 70 in the first innings, was trapped lbw by Mohammad Abbas for one and Mark Stoneman, under severe pressure for his place in the team, made a scratchy nine before he was bowled by leg-spinner Shadab Khan before England limped to lunch at 37 for two.
It was the exit of Malan, who saw a piece of his helmet fly off after turning away from a Hasan Ali bouncer, that sparked the slump.
Pakistan were soon in the wickets with Cook looking on as the other three members of England's top four all fell in single figures.
But shortly before tea Cook was bowled by Mohammad Amir, a team-mate when Essex won the County Championship last season, as the left-arm quick produced a brilliant delivery that cut away late off the pitch to clip the top of the off stump.
The ICC noticed that two Pakistan cricketers were wearing smartwatches during the first day of the Lord's Test and consequently announced the verdict to ban the use of the device.
Joe Root, the England captain, was 22 not out and Dawid Malan nought not out on his Middlesex home ground.
A frustration of the talented Root's career has been an inability to turn Test fifties into hundreds and Saturday was a case in point.
Ben Stokes, who had hoisted Shadab for six, was lbw on review to Abbas for 38.
Buttler and Bess, however, kept Pakistan at bay with Bess - whose first-class debut, against Pakistan, was just two years ago - driving Hasan Ali for four to give England the lead.