Rassie van der Dussen will come in for Moeen Ali at Islamabad United while Mujeeb ur Rahman will be replaced by Peter Hatzoglou at Peshawar Zalmi
Karachi Kings have added Adam Rossington as a partial replacement for James Vince ahead of the Pakistan Super League.
The Hampshire captain's England recall for the Bangladesh ODIs (March 1-6) means he will be absent for the seventh, eighth and ninth matches of the group phase.
Rossington, currently playing in the SA20 for Sunrisers Eastern Cape, will arrive to cover the period.
An opening batter and wicketkeeper, the Essex man has scored 2,488 runs at 21.26 in 129 T20s, at a strike rate of 145.24.
Islamabad United have also been forced into a late change with Moeen Ali - involved with England until March 14, covering the entire group stage - being replaced by South Africa's Rassie van der Dussen.
Van der Dussen played three matches in last year's IPL (Alex Davidson/Getty Images)
It will be Van der Dussen's first stint in the PSL. One of the best List A batters in the world, the right-hander's T20 record is also impressive having scored 4,505 runs at 36.62.
Mujeeb ur Rahman is on Afghanistan duty in the United Arab Emirates for the first week of the competition, with Australian legspinner Peter Hatzoglou called up as a replacement at Peshawar Zalmi.
The 24-year-old has claimed 42 wickets in 40 T20s with an economy rate of 7.79.
The eighth edition of the PSL gets underway from February 13 with a repeat of last season's final between defending champions Lahore Qalandars taking on Multan Sultans.
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