St Albans City were left to rue refereeing decisions that went against them as their unbeaten home run came to an end on Monday night at the hands of Cambridge City.

Adam Marriot’s 15th minute free-kick proved to be the difference between the two sides but City saw a “stonewall” penalty waved away and Ryan Wharton was given his marching orders for two bookable offences, neither of which warranted a booking.

The game started at a frantic pace but Cambridge settled better and had the first chance of the game. James Brighton smashed the ball from 35 yards, it hit the post, Paul Bastock’s back and looked to cross the line but the referee waved play on and Ben Martin cleared.

The opener wasn’t long coming though as Marriot curled a free-kick from the edge of the area into the top corner.

City struggled to find a foothold in the game as the players’ first touch frequently went wayward and their passing was too often off target.

They improved in the latter stages of the half and should have been awarded a penalty in injury time. John Frendo worked his way into the box and knocked it past the defender who tripped him, but the referee waved away the home teams’ protestations.

New signing Victor Osobu from Beaconsfield made his debut, replacing Chris Watters, and injected some pace into City’s attacking play.

Both teams then had chances to score. First Cambridge’s Josh Dawkins headed wide and a deep cross found him unmarked at the back post, and then Richard Graham hacked wide from inside the box.

Saints continued to craft out chances, Frendo having the best of them, but the wind was taken out of their sails when Wharton was dismissed. He challenged for a header and the referee adjudged him to lead with his arm and sent him off.

Chris Henry was introduced with 10 minutes left but City couldn’t find him in space to work his magic. The best opportunity to equalise fell to Martin who forced Zac Barrett into a diving save but City ran out of time and Cambridge claimed all three points.