Leeds, May 19 Alex Hales and Jonathan Bairstow frustrated Sri Lanka after debutant all-rounder Dasun Shanaka sparked a top-order collapse on the first day of the first Test at Headingley today. England, who had slumped to 83-5, were 171-5 at tea, with rain threatening to stop a prompt resumption of a fascinating day’s play. Opening batsman Hales, under pressure for his place after a modest return in England’s series win in South Africa, was a Test-best 71 not out with Bairstow, on his Yorkshire home ground, unbeaten on 54. The pair’s so far unbroken sixth-wicket stand of 88 helped England recover after Shanaka’s treble strike went a long way to justifying Sri Lanka captain Angelo Mathews’s decision to field first. Mathews won the toss in overcast conditions reminiscent of those at Headingley two years ago when his side won the second Test to seal their first series win in England. England captain Alastair Cook, who started his innings needing just 36 more runs to become the first Englishman to score 10,000 in Tests, got off the mark with a trademark clip off his legs for four. But the left-handed opener was caught behind for 16 going for a cover drive off a wide but full delivery from Shanaka. Three deliveries later and still in the 21st over, Shanaka had the under-fire Nick Compton out for nought with first slip Lahiru Thirimanne holding a low catch. Joe Rootalso fell for a duck to Shanaka as he edged to gully. Shanaka had taken three wickets for one run in eight balls, again proving the value of accurate medium pace.