Rain and gloom delayed the start of the fourth day of the first Test between New Zealand and South Africa in Dunedin on Saturday.
The covers were removed in time for a start a few minutes late, but were put back on as further drizzle fell while the players warmed up.
"In the interest of getting a result we need to be cautious," umpire Bruce Oxenford told reporters.
The forecast is for cold but mainly fine weather on Saturday but heavy rain on Sunday.
South Africa are 38 for one in their second innings, ahead by five runs with nine wickets in hand.