The Blues needed all their defensive know-how to survive a strong finish from the home team.
Coach Leon MacDonald said: "We were really disappointed with that second half. We'd worked our way into the game after an indifferent start, and had wrestled some momentum back with patient, controlled attack, rewarded with three well-taken tries."
Ahead 22-8 at halftime, MacDonald said they were well-positioned. But a missed kick for the corner was a harbinger of misfortunes for the remainder of the half.
"We starting stacking errors, and giving momentum away, and this competition is too tight to do that," he said.
Although the Blues' defence proved sufficient to deny the Force an upset, MacDonald said tackle loads of 29 tackles by captain, and flanker, Dalton Papalii and 24 by No8 Anton Segner were too much.
"We don't want our skipper making that many tackles. It's not sustainable, though we are pleased and proud of what he [Papalii] can do defensively. We've got to be better.
"We're going to end up getting our key players injured if we're not smarter with the way we're playing," he said.
Poor discipline put pressure on, although MacDonald said it would not take big adjustments to resolve that.
"Half a metre with our offside line would have made a difference, and, sometimes, we're not quite on balance at the breakdown."
When it came to the crunch in the final moments, the Blues withstood 26 phases of the Force driving at the line, and didn't yield.
"The referees were watching closely, and we didn't give them anything. We can do it when we are tuned into it. We just weren't tuned in enough," he said.
Adjusting that would allow more chances to attack rather than having to defend.
Akira Ioane's return to the blindside flank was welcome.
"He got through some decent work, some good carries, scored a well-taken try and was trying to be busy on attack and defence. His foot came through well. He'll be better for that hitout.
Second five-eighths Roger Tuivasa-Sheck continued his growth, contributing to two of the side's tries.
"He brought energy and work-rate and looked like he was enjoying it.
"In the first half, we balanced being direction with strong carries and cleans, and were able to give guys like Roger space to move with. That's our game when we do it right," he said.