Younis Khan took advantage of a flat pitch at the National Stadium to become only the third Pakistan batsman to score a triple hundred, steering his side out of trouble in the first Test against Sri Lanka [Images] Tuesday.

Younis ended the day on 306 not out as Pakistan reached 574 for five on the fourth day in reply to Sri Lanka's first innings total of 644 for seven declared.

With the Test heading for a draw, Younis will have West Indian great Brian Lara's [Images] Test record of 400 in sight on the final day of the match.

The Pakistan captain's marathon innings has so far spanned 731 minutes, 545 balls and included 27 fours and four sixes.

He followed Hanif Mohammad (337) and Inzamam-ul-Haq [Images] (329) into the 300-run Pakistan club.

Younis and his Sri Lankan counterpart Mahela Jayawardene [Images], who scored 240, also set a new benchmark as it was the first time rival captains had scored double hundreds in the same Test.

Younis reached his triple ton after reverse sweeping Muttiah Muralitharan [Images] and running three runs.

His coach, former Test player Intikhab Alam, said it was the best innings he had seen by Younis.

"The pitch is flat but the spinners were skidding the ball and it was not easy to score runs. A 300 even on a cement wicket is a feat to reckon with," Alam said.

In an impressive display of endurance and concentration, Younis bowed his head after reaching the landmark while the small crowd gathered at the stadium gave him a standing ovation.

The blistering knock by Younis, who also became the sixth Pakistani to reach 5,000 runs in Test cricket, ended any hopes Sri Lanka had of winning the match.

On a frustrating day for the visitors, Sri Lanka picked up only two wickets Tuesday. Overnight batsman Misbah-ul-Haq fell leg before to Dilhara Fernando for 42 and Faisal Iqbal [Images] (57) was also trapped lbw by Jayawardene.

Misbah helped his captain add 130 for the fourth wicket while Faisal shared a 174-run stand in 274 balls for the fifth wicket with Younis.

Younis who resumed on 149 on the fourth day also became the first batsman to score a triple hundred against Sri Lanka and also the first Pakistani captain to score 300 runs.

Wicketkeeper Kamran Akmal was unbeaten on 27 at the close.