The mathematics were still causing a few heads to be scratched after Arsenal's 3-0 victory over Dinamo Zagreb on Wednesday, but Declan Rice gave the new Champions League format a thumbs up.

"It's been really, really good. It's the first time trying it out and I think everyone was a little bit confused how it would work when it first got announced, but playing in this format has been really interesting," the midfielder said.

"Playing big teams, coming up against different opposition, I've really liked it."

Rice scored the opener as Arsenal made it a virtual mathematical certainty that they will finish in the top eight of the 36-team group stage which this season replaced the established format of eight groups of four.

They are in third place with 16 points and in reality can already start planning for the knockout phase, even if manager Mikel Arteta could not bring himself to say it.

"We haven't been told. I know we're in a really strong position," the Spaniard said after Arsenal extended their unbeaten home run in Europe to 15 games.

Kai Havertz took his season's tally to 14 with Arsenal's second goal and Martin Ødegaard poached his first goal since November in stoppage time to wrap up a comfortable win.

"Overall, we got the job done and well done. We didn't concede a shot on target which is really positive again. It shows that the team is really well-rounded," Arteta said. "Overall, scoring three goals, winning in the Champions League at home, another clean sheet at home -- four in a row -- and having made some changes as well.

"We rotated players that didn't play that many minutes and they responded really well."

Avoiding a Champions League playoff will also guarantee the Arsenal squad some winter sunshine as Arteta said a break is now likely to recharge batteries seeing as they are already out of the FA Cup, which continues on Feb. 7-11.

"It was very helpful [last season] and with the schedule that we've had for the last three months, you can have a break, reset a little bit and work on things and rest some people, while some people are back, that would be great," he said.