HARARE - Dimuth Karunaratne's fourth Test century helped Sri Lanka build a formidable lead before rain thwarted their victory push over Zimbabwe in the first Test on the fourth day at Harare Sports Club on Tuesday.

Karunaratne backed up his half-century in the first innings with 110 in the second, which allowed Sri Lanka to progress to 247 for six when the rain arrived just 3.5 overs into the final session. With a lead of 411, the tourists would have hoped to declare and have a bowl at the Zimbabwean top order, but while the rain lasted less than an hour the light failed to improve and so no further play was possible.

The game will restart half an hour earlier on the final morning, at 09:30am local time. "We have a whole day tomorrow and we'll give a good fight," said Karunaratne. The Zimbabweans were able to restrict the Sri Lankan scoring early on the fourth morning as the tourists resumed on five without loss, with fast bowler Carl Mumba bowling Kaushal Silva in the seventh over of the day.

But Karunaratne gradually opened up, and added 55 brisk runs for the second wicket with Kusal Perera.

Although Perera fell for 17 when he edged a delivery from Malcolm Waller to slip, and Mumba dismissed Kusal Mendis and Upul Tharanga either side of the lunch break, Karunaratne was able to maintain a steady scoring rate with Dhananjaya de Silva, who made 64 in 82 deliveries. Karunaratne was eventually caught and bowled by Chris Mpofu in the lead-up to tea, while De Silva became Mumba's fourth victim shortly after the break, giving the debutant figures of 4 for 50.

But with Sri Lanka closing in on a declaration, bad light and then rain took hold, leaving Zimbabwe with less time to hold out for the draw.

 "One of the ways we've improved is in being able to force the opposition to take the game even longer," said bowling coach Makhaya Ntini.

Scoreboard

aSRI LANKA 1ST INNINGS: 537 ALL OUT

ZIMBABWE 1ST INNINGS: 373 ALL OUT

SRI LANKA 2ND INNINGS:

D Karunaratne c & b Mpofu 110

K Silva b Mumba 7

K Perera c Masakadza b Waller 17

K Mendis c Cremer b Mumba 19

U Tharanga c Moor b Mumba 1

D de Silva c Waller b Mumba 64

A Gunaratne not out 16

D Perera not out 1

EXTRAS: (6b, 5lb, 1nb) 12

TOTAL: (6 wkts, 61.5 overs) 247

FOW: 1-17, 2-72, 3-111, 4-117, 5-211, 6-241

BOWLING: Mpofu 16-2-42-1, Cremer 14-0-67-0, Mumba 111.5-2-50-4, Tiripano 8-0-33-0, Waller 5-0-17-1, Williams 1-0-5-0, Masakadza 6-1-22-0.

TOSS: Sri Lanka

UMPIRES: Ian Gould and Simon Fry

TV UMPIRE: Jeremiah Matibiri (ZIM)

MATCH REFEREE: Chris Broad (ENG)