Leg-spinner Devendar Bishoo took a career best six wicket haul but Pakistan still swelled their lead over West Indies on the fourth day of the first Test in Dubai on Sunday.
Bishoo returned with figures of 6-47 in 13 overs as Pakistan stuttered to 121-8 at dinner - having an overall lead of 343 with two wickets in hand as the Dubai stadium pitch took sharp turn on the penultimate day of the day-nighter.
Earlier it was Pakistani leg-spinner Shah who became the second joint-fastest bowler to take 100 wickets in Test cricket during his 5-121 which bundled West Indies out for 357 in their first innings.
Pakistan, who scored 579-3 declared in their first innings, did not enforce the follow-on despite West Indies coming up 23 runs short of the follow-on target of 380.
At tea Sarfraz Ahmed was not out on 15 while Yasir Shah was dismissed for two as Pakistan collapsed in search of quick runs to effect a 1-0 lead in the three-match series.
With the rough marks on the pitch helping spinners, Bishoo triggered a middle-order collapse after Pakistan had lost opener Azhar Ali (two) and Asad Shafiq (five) just before tea.
Bishoo, who had trapped Shafiq leg-before ahead of tea, then came into his own, dismissing Babar Azam (21), Sami Aslam (44), Misbah-ul-Haq (15), Mohammad Nawaz (nought) and Wahab Riaz (five) in the space of 40 balls for 21 runs.
Bishoo's previous best bowling was 6-80 against Australia at Dominica last year.
Ali, who scored a career best 302 in the first innings, was lucky to avoid a caught behind decision off Gabriel but was trapped leg-before the very next ball. The day also belonged to Shah who wrapped up the West Indies innings in quick time and also reached a milestone. England's right-arm medium-pacer George Lohmann reached 100 Test wickets in just 16 Test matches in 1896, which still is a world record in Test cricket's 140-year history.
Australia's Charlie Turner and Clarrie Grimmett, and England's Sydney Barnes each got to the milestone in their 17th Test.
Shah, who made his debut at the same venue in October 2014, bettered off-spinner Saeed Ajmal who held the Pakistani record of fastest to 100 Tests wickets in 19 matches.
West Indies's overnight batsmen Shane Dorwich (32) and Jason Holder (20) both fell to Shah while Bishoo (17) fell to Nawaz as West Indies failed to delay the inevitable.
Nawaz finished with 2-30 on debut and Riaz took 2-65.
The remaining two Tests will be played in Abu Dhabi (October 21-25) and Sharjah (October 30-November 3).
Scores after Pakistan's second innings on the fourth day of the first Test, a day-nighter, against West Indies at Dubai stadium on Sunday:
Pakistan, first innings 579-3 declared (Azhar Ali 302 not out, Sami Aslam 90, Babar Azam 69, Asad Shafiq 67)
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West Indies 1st innings (overnight 315-6)
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K. Brathwaite lbw b Y. Shah 32
L. Johnson lbw b Y. Shah 15
D. Bravo c Ali b M. Nawaz 87
M. Samuels lbw b Sohail 76
J. Blackwood c S. Ahmed b W. Riaz 37
R. Chase c Azam b W. Riaz 6
S. Dowrich lbw b Y. Shah 32
J. Holder b Y. Shah 20
D. Bishoo b M. Nawaz 17
M. Cummins b Y. Shah 0
S. Gabriel not out 6
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Extras: (b9, lb8, nb11, w1) 29
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Total: (all out; 123.5 overs) 357
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Fall of wickets: 1-42 (Johnson), 2-69 (Brathwaite), 3-182 (Samuels), 4-259 (Blackwood), 5-266 (Chase), 6-300 (Bravo),
7-325 (Dowrich), 8-346 (Holder), 9-351 (Cummins)
Bowling: Amir 22-6-54-0 (2nb), Sohail 16-2-56-1, Shah 43-15-121-5, Riaz 23.3-3-65-2 (8nb, 1w), Nawaz 16.5-5-38-2 (1nb), Ali 2.3-1-6-0
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Pakistan 2nd innings
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S. Aslam c Blackwood b Bishoo 44
A. Ali lbw b Gabriel 2
A. Shafiq lbw b Bishoo 5
B. Azam b Bishoo 21
M. Haq b Bishoo 15
S. Ahmed st Dowrich b Bishoo 15
M. Nawaz b Bishoo 0
W. Riaz c Brathwaite b Bishoo 5
Y. Shah c and b Holder 2
S. Khan not out 1
M. Amir b Bishoo 1
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Extras: (b10, nb2) 12
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Total: (all out; 31.5 overs) 123
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