|Second Test, Karachi (day four of five);|
|Pakistan 191 & 555-3dec: Abid 174, Masood 135, Azhar 118, Babar 100*|
|Sri Lanka 271 & 212-7: Fernando 102*, Dickwella 65; Shah 3-31|
|Sri Lanka need 264 runs to win|
Pakistan became only the second team in history to have their top four batsmen all score a century in an innings as the hosts closed in on victory over Sri Lanka in the second Test.
Captain Azhar Ali (118) and Babar Azam (100 not out) reached their tons on day four after openers Shan Masood (135) and Abid Ali (174) did so on day three.
Pakistan declared on 555-3 to set Sri Lanka 476 to win in Karachi.
The tourists slipped to 212-7 at the close, still needing 264.
Sri Lanka opener Oshada Fernando remains unbeaten on 102, but Pakistan require just three wickets on day five to win the two-match series after the first Test ended in a draw.
Wicketkeeper Niroshan Dickwella scored 65 for the tourists but no other batsman offered Fernando enough support as 16-year-old Pakistan fast bowler Naseem Shah claimed 3-31.
The only previous instance of the top four batsmen all scoring a century in a Test innings came when India's Dinesh Karthik, Wasim Jaffer, Rahul Dravid and Sachin Tendulkar all hit tons against Bangladesh in Mirpur in 2007.
That came in the first innings, so Pakistan are the only side to achieve the feat in the second innings of a Test.
This is the first Test series in Pakistan since the Sri Lanka team bus was ambushed by gunmen in Lahore on 3 March 2009, when six policemen and two civilians died and several Sri Lanka players and coaches were injured.