Daniil Medvedev was asked by the umpire not to shout at a line judge during his second-round victory over Gael Monfils at the Monte Carlo Masters.

The 2021 US Open champion was leading 6-2 1-2 when he angrily disagreed with two calls on the baseline and vented his displeasure at the official.

Swedish umpire Mohamed Lahyani twice came on to court to check calls and calm down Russian fourth seed Medvedev.

“Daniil please don’t shout at him,” Lahyani said. “He (the line judge) can make a mistake as well.”

Medvedev was 40-15 up in that game but lost his serve and then went 4-1 down before winning five games in a row to seal a 6-2 6-4 success and progress to a last-16 meeting with compatriot Karen Khachanov.

The disagreement began when a shot from Monfils, which Medvedev returned with a forehand winner, was called out.

Lahyani came out of his chair to check the call but said it was in and awarded the point to the Frenchman before Hawkeye showed the ball was in fact out.

On the following point, Monfils’ shot was called in when it had travelled beyond the baseline.

A frustrated Medvedev then began to shout and this time the umpire agreed with him.

The world number four continued to remonstrate during the change of ends and was pictured hitting the canopy of his chair.

When Lahyani said he would apologise if he was wrong, Medvedev replied: “How can you apologise, I lost the freaking game. How did I lose the game when it’s out? It’s out, it’s out.”