The 27-year-old has admitted that City's clash with Liverpool on Sunday will be the Citizens most hard challenge on the road this season.
The Citizens, meanwhile, have also only dropped two points so far this term and head into this weekend's game top of the table on goal difference, and level on points with Liverpool FC.
"Even if they'd lost I'd say it was a good performance, but Napoli worries me".
"I thought Liverpool were very good against Chelsea", Neville said on Sky Sports' Friday Night Football.
Comparison between Liverpool's Mohamed Salah and Manchester City poacher Sergio Aguero is premature, according to Pep Guardiola who believes the Egypt forward would need to replicate his last season form in "eight or nine years".
Defender Walker added: "We're the champions and we have a point to prove". We beat them at home last season but at Anfield we weren't able to play well enough to beat them.
The Belgian was expected to be out for three months but returned to training earlier this week. "They are a top side".
Rams run Vikings out of LA
That's not to say that Goff's group can't get it done, just right now, I'd go with the trust factor, and that's Minnesota for me. Cousins played well enough for the Vikings to win on Thursday, completing 36 of 50 passes for 422 yards and three touchdowns .
City's all-time goalscorer Aguero has 111 top-flight goals  more than Salah , who hopes to outshine the former Atletico Madrid striker at Anfield on Sunday.
Goals seem to be on the agenda when these two meet and while both teams to score looks a good option, I don't see much value in the price at around [1.56] despite thinking it may well occur, I think I would prefer to look elsewhere for a bet. "That was that day, and they will try to strike back".
Man City will also make a late assessment on Kevin De Bruyne after he returned to training last week following two months out with a knee ligament injury but the Belgian global may only be fit enough for the bench.
He said: "Obviously we won the last three games against City". We're playing the best team in England and arguably one of the best teams in Europe and the world right now.
Liverpool registered three wins over Man City last season. After none of these games you go into the dressing room and think, "Now we know how to beat Manchester City", because there is no real way, no one thing that you have to do.