In-form batsman Mohammad Hafeez and struggling opener Fakhar Zaman are absentees from the Pakistan squad named by selectors Sunday for the Twenty20 international series against South Africa next month.
The 40-year-old Hafeez is in the form of his life, scoring 502 runs in his last 12 Twenty20 internationals at an average of 100.40 with a strike rate of 153.
But chief selector Mohammad Waseem said the senior batsman was not available for the series.
"There are no questions over Hafeez's performance, but he has not given his availability on February 3 when the squad will go in a bio-secure environment," said Waseem while announcing the squad.
Hafeez is currently featuring in the T10 league in Abu Dhabi, which finishes on February 6.
Pakistan and South Africa will play three Twenty20 matches -- all in Lahore -- on February 11, 13 and 14.
Waseem said current form, as well as this year's Twenty20 World Cup in India, were considered for selection.
Zaman was in a poor form, having managed just 97 runs in his last ten matches. He also missed the Twenty20 series in New Zealand in December following a positive Covid-19 test.
Babar Azam will lead the squad, which also sees comebacks for pacer Hasan Ali, all-rounder Aamer Yamin and batsman Asif Ali.
Uncapped leg-spinner Zahid Mahmood, all-rounder Amad Butt and batsman Danish Aziz are also part of the 20-man squad, while pacer Wahab Riaz is left out.
Pakistan lead the two-match Test series 1-0 after beating South Africa by seven wickets in Karachi on Friday.
They begin the second Test in Rawalpindi on Thursday.
Squad: Babar Azam (captain), Haider Ali, Khushdil Shah, Hussian Talat, Danish Aziz, Asif Ali, Iftikhar Ahmed, Mohammad Nawaz, Zafar Gohar, Faheem Ashraf, Aamer Yamin, Amad Butt, Mohammad Rizwan, Sarfaraz Ahmed, Shaheen Shah Afridi, Haris Rauf, Mohammad Hussain, Hasan Ali, Usman Qadir, Zahid Mahmood