Alastair Cook completed his third Test double-century as England eased past the follow-on mark, and a stalemate loomed against Pakistan at the Zayed Cricket Stadium.
Cook (201no) achieved the feat after more than 10-and-a-half hours at the crease in the first Test, as he and Joe Root (74no) helped England to 394 for three in reply to 523 for eight declared shortly before lunch on day four.
The England captain's innings was rising up the top-10 charts among his country's all-time longest when, from the 395th ball he faced, he clipped Wahab Riaz for two behind square on the leg-side to move to 200.
Cook had a minor moment of fortune, only his second after being dropped the previous evening, when on 173 this time he inside-edged Wahab low to diving wicketkeeper Sarfraz Ahmed.
It was barely a half-chance, which did not stick and would have been a brilliant catch if it had.
Pakistan's bowlers began well, and it took almost 11 overs before Cook counted England's first boundary of the morning - a sweep off Zulfiqar Babar.
Root followed up with a cover-driven four in the next over, off Imran Khan, and then an inside-edge inches past his off-stump which also beat Sarfraz to take the deficit under 200.
Imran was disappointed again two balls later when Root survived an lbw review on 24, his advance down the pitch helping to save him via umpire's call.
But the Yorkshireman became more assured on the way to an 83-ball 50, completed when he reverse-swept Shoaib Malik for his fifth boundary.