Graeme Smith scored a half-century but fell late on as South Africa made a confident reply after dismissing Sri Lanka for 180 on the opening day of the first test on Thursday.Seam bowler Vernon Philander claimed five wickets for the hosts, who reached 90 for one at the close at Centurion.South Africa captain Smith looked in fine form as he stroked seven fours in his 61 — his 30th half-century in his 94th test — but played around a full delivery from Dilhara Fernando to be trapped lbw. Opening partner Jacques Rudolph was unbeaten on 27. Sri Lanka’s bowers were steady, but they struggled to obtain the same assistance the South Africans did, even though the home attack sprayed the ball around disconcertingly at times. South Africa’s much-vaunted attack were struggling in helpful conditions as Thilan Samaraweera and Angelo Mathews added 65 for the fifth wicket off just 80 balls.The pair took Sri Lanka to 156 for four before Philander struck three times in four overs to complete his third five-wicket haul in three tests. Philander’s destructive burst began with two wickets in successive deliveries, both given out on review, as Samaraweera (36) edged an excellent delivery that nipped away off the seam and Kaushal Silva was adjudged to have brushed the ball with his glove as it flew to wicketkeeper Mark Boucher down the leg side.Thisara Perera took a single off the hat-trick ball, but only lasted until the next over when he failed to read an Imran Tahir googly and Jacques Kallis made a stunning reflex catch at slip as the edge bounced off Boucher’s thigh. Sri Lanka had lost three wickets in five balls to slump to 157 for seven and Philander struck again to have Mathews caught by Kallis for 38.