"We had to name a 17-man squad after taking into account injuries to some key players with Gul ruled out due to back problem," Chief Selector Wasim Bari said on Friday.
Gul, who was adjudged Man of the Match after picking 5 for 31 in India's first innings in the Lahore Test which Pakistan won, is suffering from cramps, said Bari.
Wicketkeeper Moin Khan, Shabbir Ahmed, Saqlain Mushtaq and all-rounder Abdul Razzaq, who did not play the Lahore Test, were once again left out of the squad which has four pacers, who have not had a look-in the Test series so far, in Rao Iftikar, Abdul Rauf, Rana Naved-ul Hasan and Fazle Akbar.Spinner Shoaib Malik, who did not play the first two Tests but featured in the One-dayers, has been drafted in the squad.
Bari said Gul could bowl in the second innings in Lahore only after taking pain-killing injections and he was not match-fit.
Gul said he was disappointed at being missed out.
"I am really disappointed for missing out because I was geared up but this injury has forced me out," he said.
Bari said, "Injuries are part and parcel of the game and are unavoidable but I hope that the boys cope with the situation and do their best as they did in the Lahore Test".
Pace bowler Shabbir is nursing a shin injury. Moin and Razzaq played in the first Test at Multan but pulled out of the second Test with Moin suffering a groin injury and Razzaq having a back problem.
Bari admitted he was concerned with the injuries to the frontline players ahead of the crucial Test.
"Injuries are concerning, but I am confident that the boys will put this behind them and display the same standard of cricket that earned them victory," Bari said.
"We will sit down again on April 11 to reduce the squad to 15," said Bari.Of the new inclusions, only Akbar has played for Pakistan before with his last of two Tests against New Zealand in 2001 and his last of four One-day games in England the same year.
Iftikhar and Hasan are leading wicket-takers in Pakistan's last domestic season while Rauf is a fast rising fast bowler who bowls at around 90 miles per hour.
The three-match series is levelled at 1-1 with India winning the first Test at Multan by an innings and 52 runs and Pakistan squaring the series with a nine-wicket win in the second at Lahore.
17-member squad: Inzamam-ul-Haq (captain), Taufeeq Umar, Imran Nazir, Imran Farhat, Yasir Hameed, Yousuf Youhana, Asim Kamal, Misbah-ul-Haq, Kamran Akmal (wk), Shoaib Akhtar, Mohammad Sami, Danish Kaneria, Shoaib Malik, Rao Iftikhar, Anjum, Fazle Akbar, Abdul Rauf, Rana Naveed-ul-Hasan.