On a flat, even batting pitch, the West Indies won the toss but again their middle-order batting let them down and they lost their last five wickets for just 56 runs.
Instead, Ijaz Ahmed and Aamer Sohail got Pakistan's reply off to flying start, adding 34 runs without loss before bad light stopped play. Aamer was unbeaten on 20, which included two cracking cover boundaries off Franklyn Rose, while Ijaz was not out on 11.
Saqlain, the 21-year-old off-spinner, did not play in the first two Tests but proved his worth by claiming his third five- wicket haul in his 13th Test and also completed 50 wickets in Test matches during his spell of 5-54, bettering his 5-89 against Sri Lanka earlier this year.
The day was shaping up somewhat differently when Sherwin Campbell and Stuart Williams put on 47 runs in nine overs at the top of the West Indies order. However, Williams was brilliantly run out by Mushtaq Ahmed with a direct hit from mid-off as the openers attempted a needless run. Williams, who had failed to reach double figures in his previous four Test innings, made a rapid 33 off 33 balls which included six boundaries.
Campbell was dropped by Aamer at second slip off Wasim Akram on 14, and he and Brian Lara went on to compile 62 runs in 94 minutes for the second wicket.
Lara fell shortly into the second session, bowled by Mushtaq. Hooper got a second duck in his last three innings when he was leg before to leg-spinner Mushtaq.
Shivnarine Chanderpaul briefly stayed together with Roland Holder and hit four fours in his 21 before Akram had him trapped leg before in the second spell.
West Indies - First innings
S L Campbell c Aamer b Saqlain 50
S C Williams run out 33
B C Lara b Saqlain 36
C L Hooper lbw b Mushtaq 0
S Chanderpaul lbw b Wasim 21
R I C Holder b Saqlain 26
D Williams not out 22
I R Bishop st Moin b Saqlain 2
F A Rose lbw b Wasim 13
*C A Walsh c Inzamam-ul-Haq b Saqlain 1
M Dillon b Wasim 0
Extras (b4 lb7 nb1) 12
Total (73.1 overs) 216
Fall of wickets: 1-47, 2-109, 3-114, 4-126, 5-160, 6-188, 7-194, 8-209, 9-212.
Bowling: Wasim 17.1-2-76-3; Waqar 9-3-21-0; Azhar 10-3-14-0; Mushtaq 13-2-40-1; Saqlain 24-6-54-5.
Pakistan - First Innings
Aamer Sohail not out 20
Ijaz Ahmed not out 11
Extras (lb2 nb1) 3
Total (for 0, 8.3 overs) 34
To bat: *Wasim Akram, Saeed Anwar, Inzamam ul-Haq, Moin Khan, Azhar Mahmood, Saqlain Mushtaq, Mohammed Wasim, Waqar Younis, Mushtaq Ahmed.
Bowling: Walsh 4.3-2-10-0; Rose 4-0-22-0.
Umpires: Cyril Mitchley (Rsa) and Salim Badar (Pak).