There were mixed fortunes for CIYMS on the opening day of the European Cricket League in Spain.
They began strongly to brush aside the challenge of Swedish side AKIF by ten wickets.
Former Ireland A international Allen Coulter took the bowling honours with 3 for 21 as the Swedes were restricted to 83 for 9.
Irish leg-spinner Jacob Mulder claimed two wickets for just six runs, while skipper John Matchett had 2 for 21.
The chase was a routine one with Man-of-the-Match Jason van der Merwe clubbing four sixes and three fours in an unbeaten 44 from 21 balls.
Jason van der Merwe ©CricketEurope
The former Ireland U19 international shared an unbroken opening stand of 84 in 5.5 overs with Chris Dougherty - who hit 3 sixes in his unbeaten 32 from 16 balls.
However, in the afternoon game they were brought back down to earth as they were edged out by Portuguese side Oeiras by eight runs.
Allen Coulter was again in the wickets, claiming four for seven, with Mulder taking 2 for 11.
However Miguel Machado took a shine to Carson McCullough, hitting five sixes in a whirlwind 48 as the Portuguese champions finished on 101 for 8.
Dougherty, Matchett and Van Der Merwe went early to put the Belfast side in bother, and at 43 for 4 at the halfway stage, there was plenty to do.
Carson McCullough (40) and former Ulster rugby player Mark Best (23) both hit two sixes in a stand of 43 in four overs, but they were always just a little behind the required rate.
A flury of late wickets including Mulder and Coulter first ball ensured their fate, much to the delight of the underdogs.
CIYMS are back in action on Friday, playing Istanbul in the morning and Punjab from Cyprus in the evening.