Hello, and welcome to tonight’s liveblog.

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The team news is below with Messi, Suarez and Neymar all restored to Barca’s starting XI.

We’re underway…

Celtic have started this match aggressively.

The hosts haven’t been afraid to press Barcelona high up the field.

Scott Brown has launched into a hard tackle on Busquets.

It looked late and surprisingly, the ref waves play on.

Dembele’s header deflects off Mascherano and goes out for a corner.

It’s been an encouraging start for Celtic.

Celtic breathe a sigh of relief.

Messi finds space inside their box, but his shot deflects away from goal.

Another chance is wasted by Barca.

Busquets picks out Messi with a lovely lofted through pass, but for once, the Argentine international fails to control the ball adequately.

Celtic are causing Barca plenty of problems in their final third, with the visitors guilty of a few stray passes.

As I type though, Alba crosses to Messi, who fails to hit the target with his side-footed finish.

Dembele finds himself in a promising position, but his pass to McGregor is rushed and Celtic concede possession.

Down the other end, Rakitic heads Suarez’s cross just wide.

It’s been a highly entertaining end-to-end opening to this match.

Barcelona are increasing the pressure now.

Celtic have been defending nervously from corners, with Gordon having to be alert from Gomes’ flick-on.

CELTIC 0-1 BARCELONA (MESSI 24)

It’s been coming!

Neymar plays an intelligent through pass and Messi beats Gordon at the near post with a clinical first-time finish.

I think he’s lightweight at this level.”

Chris Sutton is questioning Brendan Rodgers’ decision to pick Callum McGregor ahead of James Forrest.

Here’s a look at that Messi goal.

Good attempt by Dembele.

His powerful shot is collected by Ter Stegen at the second attempt.

Just the three attempts on target so far — two from Barca and one from Celtic.

That’s not indicative of how the match has panned out — it’s been a very open game at times.

Dembele sprints towards goal but Mascherano stops him in his tracks with an excellent tackle.

The young striker has looked dangerous this evening.

Great save by Gordon to stop Suarez’s header from a Messi cross.

Down the other end, Alba gets booked for a cynical challenge to stop Sinclair on the counter attack.

HALF-TIME: CELTIC 0-1 BARCELONA

So half-time and it’s been an entertaining game at Celtic Park.

The hosts have shown plenty of bravery pressing Barca in their final third and creating a couple of half chances largely through the visitors’ mistakes on the ball.

Yet Luis Enrique’s side have been the better team overall and you get the sense that they could get out of second gear at anytime.

A Barca goal had been coming before Messi’s clinical finish, though Brendan Rodgers’ side can be satisfied overall with an impressive performance under the circumstances.

Barcelona's Luis Suarez (centre, left) has his shot saved by Celtic's Craig Gordon (centre, right). Andrew Milligan Andrew Milligan

The second half is underway…

Armstrong passes the ball straight to Messi, but then makes a superb recovery tackle.

Meanwhile, Celtic made a change at the break — James Forrest has replaced the injured Sinclair.

As I type, McGregor finds himself in a good position on the edge of the box, but Ter Stegen gets down well to save his shot.

Huge chance for Celtic!

Forrest delivers an excellent cross but Dembele’s header is too weak and Ter Stegen saves easily.

PENALTY FOR BARCELONA!

CELTIC 0-2 BARCELONA (MESSI 56)

Messi hits his penalty straight down the medal to claim his ninth Champions League goal of the season.

It was poor defending that led to it — Izaguirre had his arms all over Suarez in the box, and the referee pointed to the spot as a consequence.

Here’s a look at that second Messi goal.

Celtic's Stuart Armstrong, left, and Barcelona's Lionel Messi vie for the ball. Scott Heppell Scott Heppell

There’s just been a nasty clash of heads between Dembele and Pique, with the latter defending a set piece.

Digne has replaced Alba for Barca, and for Celtic, Bitton has come on for Rogic.

Messi is inches away from a hat-trick.

Neymar plays it to him on the edge of the box, and the Argentine superstar beats Izaguirre before slotting the ball just wide.

Neymar is booked for a late challenge on Lustig.

Lustig squares up to Neymar and also gets a booking for his troubles.

Neymar is lucky to avoid a red card for another late challenge on Lustig.

Unsurprisingly, he’s substituted moments later, with Arda coming on in his place.

This game has hit a bit of a lull in recent minutes.

Celtic look exhausted, with Barca now controlling possession comfortably.

Messi lays it off to Suarez, who clips the outside of the post with his attempt.

The Uruguayan star has not been at his best in front of goal tonight, perhaps understandably, given that he is only just back from injury.

Armstrong gets booked for a late tackle on Messi.

Celtic look a frustrated and beaten team now.

Rakitic gets booked for  a cynical drag back on his opponent.

That rules him out of the final group game, so perhaps it was another deliberate booking.

Barcelona's Luis Suarez (right) is fouled by Celtic's Emilio Izaguirre (left) in the penalty area. Andrew Milligan Andrew Milligan

Dembele runs menacingly into the box, but loses his footing at the crucial moment.

He’s looked lively and played well without getting too much service in the lone frontman role.

FULL-TIME: CELTIC 0-2 BARCELONA

That’s all from me as Barcelona deservedly beat Celtic.

Thanks for reading and commenting, and we’ll have more reaction to follow.