Dhananjaya de Silva kept Sri Lanka's hopes alive with a defiant innings on the second day of the first Test against South Africa at St George's Park on Tuesday.

De Silva made 43 not out as Sri Lanka struggled to 181 for seven - still 105 runs behind South Africa's first innings total of 286 - before bad light ended play.

South African new ball bowlers Vernon Philander and Kyle Abbott put the Sri Lankan batsmen under pressure in seam-friendly conditions, with the first three wickets falling for 22 runs.

It looked as though a full-scale collapse was possible but Sri Lankan captain Angelo Mathews made a solid 39 before De Silva came out to bat at number seven and played an impressive innings, with assistance from Dinesh Chandimal and Rangana Herath.

It was not a wholly impressive performance by the South African bowlers. Philander and Abbott both bowled well, taking three for 35 and two for 49 respectively, but rising star Kagiso Rabada had an off day.

Rabada struggled to find his rhythm and conceded 63 runs in 13 overs, although he did take the key wicket of Mathews, caught low down at third slip by Dean Elgar.

De Silva, playing in only his sixth Test, showed some of the quality that has already brought him centuries against Australia and Zimbabwe, although he survived a caught and bowled chance to left-arm spinner Keshav Maharaj when he was on 27. When play ended he had faced 69 balls and hit five fours.

The day started well for Sri Lanka when fast bowler Suranga Lakmal, playing in his 32nd Test, took his first five-wicket haul in Test cricket, finishing with five for 63, as South Africa lost their last four wickets for 19 runs.

SCORES IN BRIEF

SOUTH AFRICA: First innings 286 (Cook 59, Elgar 45, Amla 20, Duminy 63, Du Plessis 37, De Kock 37; Lakmal 5-63, Pradeep 2-66, Herath 2-48)

SRI LANKA: First innings 181 for 7 (Mathews 39, Chandimal 28, de Silva 43 not out, Herath 24; Philander 3-35, Abbott 2-49)