Xhaka let fly from 25 yards, with late movement from the strike beating Mignolet, although the goalkeeper really ought to have done better, and a delightful goal then put Arsenal in front.
"Liverpool's stutters have come at Anfield but on the road they have been magnificent, winning their last four and scoring 16 goals along the way".
A draw was certainly the fairest outcome in a thrilling contest, with Firmino's intervention ensuring Arsene Wenger is yet to beat Klopp's Liverpool in five attempts.
Last season's double over Arsenal was their first since 1999-2000 and included a 4-3 Liverpool win at the Emirates on the opening weekend of the campaign.
The points were shared at the Emirates Stadium as Arsenal and Liverpool drew 3-3 in an entertaining game in the capital.
"A point at Arsenal is a good result for most teams in the world but it feels not too good at the moment".
The big surprises in Nicholas' team were the choices of Joe Gomez at right-back, Dejan Lovren in central defence and Jack Wilshere in central midfield.
He said: " We didn't do ourselves justice in the first half.
But on a night when defensive and goalkeeping calamities showed why Arsenal and Liverpool are already out of the title race at the midway point, the hosts could not hold on to the lead.
Mohamed Salah says that he is confident Liverpool will know success in one of the competitions they are involved in this season.
Arsenal were unable to nullify the visitors, though, and the Reds got back on terms through Firmino's left-footed shot in the 71st minute.
The Gunners were annihilated 4-0 in the reverse fixture back in August, hence they would want to set the record straight and take a leap back into top four with a win tonight.