Somerset have signed all-rounder Roelof van der Merwe for the first half of their FL t20 campaign.
The 26-year-old South African will fill in for Kieron Pollard, who will miss the first eight group matches while away on West Indies international duty.
"Roelof is a big-hitting batsman, excellent fielder and bowls slow left-arm deliveries," said director of cricket Brian Rose.
"I believe he will prove an excellent signing," he added.
"Knowing that Kieron was not going to be available for a while, we looked at other options in terms of an overseas player, who could bat at six, field well and also bowl effectively in the tournament."
Van der Merwe, who has played 13 one-day and 13 Twenty20 internationals for his country, will feature as one of the club's two overseas signings alongside Murali Kartik.