Cardiff Blues fought back from being 12-0 down within the first six minutes, but were ultimately edged out by Connacht in their PRO12 clash at the Arms Park.
Gavin Duffy and Willie Faloon both touched down for the Irish side early on, before Harry Robinson dived to score in the corner to reduce the deficit to 15-8 at half-time.
Blues No.8 Robin Copeland's try then put his side in the lead, but that lasted only four minutes before Faloon darted over to score his second.
A Rhys Patchell penalty closed the gap again, but Miah Nikora was also on target with three points, for Connacht to seal victory.
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