The senior Pakistan speedster failed a fitness test at the NationalCricketAcademy on Monday.
Gul, who last played for Pakistan in South Africa earlier this year, had undergone a knee surgery in Melbourne in May and is yet to convince the selectors he is ready for a comeback to the national team.
"Pakistan captains, Misbah-ul-Haq and Muhammad Hafeez had conveyed to the selectors they wanted Gul back in the national side for the Sri Lanka series," a source said.
"Because of this the selectors decided to have a fitness test for Gul at the NCA, where he bowled in the nets but apparently he failed to convince the selectors he had made a 100 per cent recovery from his operation and was fully match fit for international cricket," the source said.
Though Gul has resumed playing cricket in the domestic competitions but so far in the few appearances he has made he has failed to come out with a big performance.
Another source said that the medical panel of the board would reassess the rehabiliation process for Gul and he might have to undergo another fitness test soon.
"The selectors have noted that Gul has so far played in only a couple of T20 and one-day matches for Habib bank in domestic cricket and is yet to be tested in a first class match," the source said.
"Misbah was keen to have Gul for the one-day series against the Lankans but it appears as if Gul will take some more time to make a comeback to international cricket," the source stated.
Gul, 29, has taken 163 Test, 161 ODI and 74 T20 wickets in his international career.
Gul himself remained confident of a comeback when he told reporters after his test that he was feeling okay and was ready to play for Pakistan again.
Pakistan is also without tall left-arm pacer Muhammad Irfan for the Sri Lanka series as he has also suffered a hip fracture during the South Africa series.
"With the selectors due to announce the squad for the five One-day Internationals against Sri Lanka later this week it is expected they will give a call up to right arm fast bowler Muhammad Talha who has been in great form this season," the source said.
Talha featured in the abandoned Test match against Sri Lanka at Lahore in March, 2009 when militants attacked the visiting team leading to the tour being called off immediately.
But the youngster this season has been bowling fast and in his last first class match which ended on Monday he took 13 wickets.
Another pace bowler in the eyes of the selectors is Usman Khan Shinwari a left armer from Kohat who took five wickets in the National T20 championship final for departments last week.
Image: Umar Gul
Image: Hamish Blair/Getty Images
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