UPDATE 2-Cricket-Pakistan closing in on Test win in Sri Lanka

* Pakistan close third day on 71-2, chasing 168 for victory

* Hosts Sri Lanka earlier dismissed for 217

* Pakistan poised to win opener of three-match series

(Updates at close)

GALLE, Sri Lanka, July 6 (Reuters) - Left-arm pace bowler Mohammad Aamer claimed three wickets in an outstanding post-lunch spell to leave Pakistan chasing just 168 for victory in the opening test against Sri Lanka on Monday.

Pakistan bowled out the hosts for 217 and then finished the third day on 71 for two -- just 97 runs shy of their victory target having lost the wickets of Khurram Manzoor (15) and Younis Khan (3).

Opener Salman Butt was unbeaten on 28 with first-innings centurion Mohammad Yousuf on 12 with the tourists closing in on a 1-0 lead in the three-match series.

The 17-year-old Aamer followed up on his impressive first innings performance (3-74) by capturing the key wickets of Tharanga Paranavitana (49), Mahela Jayawardene (0) and Kumar Sangakkara (14) as the tourists took control.

Aamer went wicketless during a rain-shortened morning session but swung the ball both ways in the afternoon to reduce Sri Lanka to 101-5 after they had appeared comfortable on 86-2.