Perth - All Blacks winger Lelia Masaga scored a try off a lost line-out by the Western Force to clinch a 37-19 victory and keep the Chiefs perfect after three rounds of the Super 14 on Saturday.
The Chiefs led 13-6 at halftime on Hika Elliot's try, the only five-pointer of the first 40 minutes.
All three of the Chiefs wins have been on the road - a 19-18 decision over the Sharks in Durban in the first round and a 72-65 victory over the Lions in Johannesburg last week in the highest-scoring Super match.
The loss was the Force's third in a row. The last-place side is the only team in the tournament without a point after three rounds.
"We played some good football in the first half but really didn't get any reward for it," said Force captain Nathan Sharpe.
"Certainly we came out with good expectations, but we just had mistake upon mistake in the second half."
(Colin Bourke, Hika Elliot, Lelia Masaga, Tim Nanai-Williams tries; Stephen Donald 4 conversions, 3 penalties)
Western Force 19
(Ryan Cross try; James O'Connor 3 penalties, conversion; Brett Sheehan penalty).