Cape Town - Manchester United midfielder Ander Herrera believes the Red Devils are on the way towards reaching their best form after beating Arsenal on Saturday.
Jose Mourinho's men extended their run of Premier League victories to four after clinching a 3-1 win over the Gunners at the Emirates Stadium, thanks to an opener from Antonio Valencia and two goals from Jesse Lingard.
Despite the good run, United are still eight points behind league-leaders Manchester City, but Herrera is confident they can keep the pressure on City.
The Manchester derby will be a top-of-the-table clash on Saturday when United host Pep Guardiola's unbeaten team, and the hosts will be without talismanic midfielder Paul Pogba, following his sending off in the Arsenal game.
Herrera told the club's official website: "We are going to find our best moment very soon. We are second and chasing to be top of the table.
"Jesse Lingard is on fire now, Paul Pogba as well, it's a pity he got a red card.
"Romelu Lukaku didn't score [against Arsenal] but he helped us a lot. The centre-backs - Victor Lindelof is in fantastic form right now. So we are optimistic, of course."
United next next face CSKA Moscow in their final Champions League group fixture before welcoming cross-town rivals Manchester City in a top-of-the-table clash on Sunday.
Kick off is at 18:30.