The west Wales outfit went into the clash in red-hot form and on the back of an unbeaten start to the season.
But the Ospreys, who had lost all of their opening games, upset the odds to put their RaboDirect PRO12 defence back on track with a hard fought win.
Easterby admits his side did not perform and came up short in the forwards. But he reckons the Scarlets can learn the lessons of the defeat.
“It was very disappointing for us and the players are hurting right now but we have to take it on the chin and deal with it,” said Easterby.
“They put a lot of pressure on us and competed in the breakdown and didn’t get picked up for it – they certainly did a job on us.
“It didn’t help when we went a man down but they’d had the upper hand in the scrum early on and that had a bit of an impact in the first half – but all over the field we were generally second best.
“They were good at scrambling when we came back at them – the truth is we just weren’t as good as them on the day.
“But we’re not panicking, there were a few issues up front but it’s not a major concern at this stage.
“We’ve shown we can compete in our opening games across the mix of our game so we’ll keep cool heads after this initial disappointment.”
Wales fly-half Rhys Priestland endured another difficult night with the boot and missed several kicks at goal.
But Easterby insists Priestland cannot be blamed for the defeat and has backed the pivot to boot his kicking woes into touch.
“Not getting all your kicks can hurt at some stages in the season but we’re working hard and Rhys is striking the ball very well – there were just some very narrow misses inches away and off the posts,” added Easterby.
“You can’t react irrationally to things like that, we’re only four games in and we’re not getting overly concerned about it.
“The boys showed their resolve by coming back to secure a losing bonus point. We have done well to close out games so far this season so we’ll learn from this one and it will only make the group stronger.”
