Pakistan now await the winners of the other semifinal between Australia and Sri Lanka.
Riding on Kraigg Brathwaite's 85, the West Indies posted 212 and appeared on course for a place in the final when an early burst by their pacemen reduced Pakistan to 49 for four. But Hammad, as he has often done in this tournament, remained undefeated with a fighting half-century to ensure victory and a shot at the title.
India swept aside England in the fifth place play-off semifinal, scoring a seven-wicket win at Hagley Oval. Skipper Ashok Menaria grabbed four for 35 as England were bowled out for a paltry 176. With opener Akshath Reddy striking a 116-ball 94, India reached 179 for three.
Brief scores (semifinal): West Indies: 212/8 in 50 overs (Kraigg Brathwaite 85, Andre Creary 41, Shane Dowrich 55; Sarmad Bhatti 2-37, Raza Hasan 2-41) lt to Pakistan: 213/6 in 48.3 overs (Ahsan Ali 28, Rameez Aziz 39, Hammad Azam 92 n.o., Mohammad Waqas 29; Jason Holder 2-28).
Fifth-place play-off semifinals: England: 176 all out in 49.2 overs (Jos Buttler 78, Ateeq Javid 34; Jayadev Unadkat 2-26, Ashok Menaria 4-35) lt to India: 179/3 in 36.4 overs (Akshath Reddy 94, Mayank Agarwal 28; Nathan Buck 2-41).