Brendan Rodgers claimed Celtic had made "significant improvement" after they exited Europe following a 2-0 defeat to Barcelona at Parkhead.
Lionel Messi, who who scored a hat-trick in the 7-0 home win over the Hoops in the opening Group C fixture, struck from close range in the 23rd minute and doubled his tally from the spot 10 minutes after the break.
The Hoops put on a better show than they did in the Nou Camp but remain bottom of the pool with two points.
They travel to Manchester City for the final fixture, unable to finish third for a Europa League spot, while the Catalans go through to the knockout stages as section winners.
However, Celtic manager Rodgers was not too downhearted, saying: "As a coach you are looking for improvement and I thought we made significant improvement,
"I thought the way we pressed the game was very good and we won the ball back in high areas of the field and when we couldn't we got defensively very solid.
"They have huge quality but they didn't have as near so many chances as what you would normally see in the games they play so I was very pleased with the performance.
"The first goal I was disappointed with but the quality and speed of movement catches us out, but that's the level.
"We were always in the game, pushing, we had a big chance with a header and another opportunity when we broke away and then you get punished by a the penalty and at 2-0 against Barcelona, we still kept fighting and working but of course it becomes that little bit more difficult."
Source: PA-WIRE
