Peterborough United were on cruise control to speed past Arsenal in the Bristol Street Motors Trophy

It finished 3-0 to Posh as Ryan De Havilland and Malik Mothersille scored their first goals for the club either side of a Jonson Clarke-Harris tap-in. The goals arrived in a 13-minute spell either side of the break.

In truth it could have been a massive margin of victory as Posh were thwarted on numerous occasions by Arsenal goalkeeper Ovie Ejeheri.

The visitors also had chances though with Posh back up ‘keeper Fynn Talley saving a second-half penalty. He also made a couple of other fine saves in a most encouraging display.

Posh made 10 changes to their starting line-up with midfielder Archie Collins the sole survivor from Saturday’s FA Cup win. Club officials like to pay lip service to the importance of this competition, but the reality was Oxford at home with points at stake four days later was far more important.

Clarke-Harris was even given a rare start as his departure after three cracking years of service approaches. The double golden boot winner skippered the side who lined up in a 3-4-1-2 formation with David Ajiboye and Zak Sturge as wing-backs and De Havilland deployed as the number 10.

Arsenal’s youngsters were unknown to all but the biggest Gunners aficionados, although Ethan Nwaneri is the youngest player to appear in the Premier League, aged 15 against Brentford last season.

The much-changed Posh team, perhaps understandably, lacked cohesion early on with Clarke-Harris looking rusty, also understandably.

The visitors could have taken the lead in the second minute, but Josh Robinson headed wide at the far post.

Clarke-Harris settled to deliver some neat touches before he smashed a 25 yard free kick into the wall and over the crossbar.

Collins was the next to threaten after collecting a poor pass out of defence. His shot from 20 yards was weak, but a deflection forced Ejeheri into a decent save.

Mothersille’s first chance arrived on 17 minutes after De Havilland slipped him in, but he shot into the side netting with his left foot.

Arsenal carried little threat until Jimi Gower’s free kick tested the handling skills of Talley. He passed the test impressively.

Collins pounced on another defensive error to burst forward, but made a hash of a shot he took far too early.

Ejeheri then made a fine reaction stop to thwart Mothersille who had flicked a fine cross from Romoney Crichlow goalwards.

But Posh finally made the breakthrough they deserved nine minutes before the break. Crichlow robbed a dithering opponent with the ball dropping for Clarke-Harris who fed Mothersille whose neat pass was driven it at the near post by De Havilland.

And four minutes later it was 2-0, again after an Arsenal player was caught in possession, this time by Jeando Fuchs. He advanced into the area poked the ball past an advancing ‘keeper and Clarke-Harris was on hand to tap home.

Sturge was forced to make a fine defensive block as Arsenal rallied, but Posh then had two glorious chances to grab a third goal before the break.

Mothersille showed good strength, pace and control to break clear, but his finish didn’t match his approach play and Ejeheri saved comfortably.

Sturge was the next to power clear, but again Ejeheri saved well again before Mothersille’s attempt to convert the rebound was well blocked.

In contrast Talley had a quiet half, but he made a superb save in the last seconds as Robinson got the better of Sturge at the back post.

Any doubts about the final outcome were surely dispelled by a magical moment for Mothersille who raced clear onto a superb ball from Fuchs four minutes into the second half before finishing with aplomb. It was a goal he greeted with understandable joy. Fuchs pass with the outside of his right foot also drew admiring comments.

Arsenal should have pulled a goal back from the penalty spot after a trip by Jadel Katongo in the 53rd minute, but Talley made a superb low save to thwart Khayon Edwards.

Posh were soon back on top with Emmanuel Fernandez missing a sitter after good work from Clarke-Harris before the centre forward forced a fine save with a power header from a Crichlow cross.

Crichlow was again prominent 12 minutes from time when playing Mothersille through, but again Ejeheri came to Arsenal’s rescue.

Posh sent on youngsters Harley Mills and James Dornelly for the final 15 minutes and the former did well to tee up Clarke-Harris three minutes from time, but his shot was deflected over. From the corner Katongo glanced a header just wide.

Talley completed his own superb night with a terrific stop to keep out a low strike from Jack Henry-Francis after a fine flowing move in added time.

It was clean sheet Talley deserved as Posh completed a North London double to advance into the third round.

Posh: Fynn Talley, Zak Sturge (sub Harley Mills, 75 mins), Jadel Katongo, Emmanuel Fernandez, Romoney Crichlow, David Ajiboye, Jeando Fuchs (sub James Dornelly, 75 mins), Archie Collins (sub Hector Kyprianou, 46 mins), Ryan De Havilland, Jonson Clarke-Harris, Malik Mothersille,

Unused subs: Jake West, Josh Knight, Ephron Mason-Clark, Ricky-Jade Jones.

Arsenal: Ovie Ejeheri, Josh Robinson (sub Josh Nichols, 65 mins), Taylor Foran, Zane Monluois, Lino Sousa, Jack Henry-Francis, Myles Lewis-Skelly (sub Ismail Oulad M'Hand, 80 mins), Jimi Gower (sub Sebastian Ferdinand, 65 mins), Charles Sagoe Jr, Ethan Nwaneri (sub Michel Rosiak, 80 mins), Khayon Edwards

Unused subs: James Hillson, Maldini Kacurri, Osman Kamara.

GOALS: Posh – De Havilland (36 mins), Clarke-Harris (40 mins), Mothersille (49 mins).

CAUTIONS: Posh – Collins (foul), Clarke-Harris (foul)

Arsenal – Monlouis (foul).

REFEREE: Lee Swabey 7.

ATTENDANCE: 2,151.