Harambee Stars midfielder Timothy Ouma has come under criticism from former English Premier League referee Dermot Gallagher following his costly error in Charlton Athletic’s heavy 4-0 defeat to Stoke City in the Championship on Sunday.The Addicks endured a difficult afternoon at the Stoke Stadium, where Stoke City ran riot to hand Charlton their first defeat of the campaign and maintain their impressive start to the season.Download our Mozzart Sport App for more newsOuma was at the centre of attention for Stoke’s opening goal after being penalised for bringing down Stoke defender Ben Wilmot inside the box.The Kenyan midfielder was caught grappling with Wilmot during a corner, prompting referee Bobby Madley to point to the spot. ##NAJAVA_MECA_9936487##Justin Devenny stepped up and calmly converted the resulting penalty to give the hosts an early lead.The incident particularly frustrated Gallagher, who felt the infringement was avoidable and made worse by the fact that Ouma had already been warned by the referee moments before the corner was taken.Speaking during a post-match review, Gallagher compared the incident to a similar penalty awarded in Sunderland’s match against Brentford, highlighting Ouma’s failure to concentrate on the ball.“Similar to the Sunderland penalty against Brentford, isn’t it? We saw it earlier. Tim was not looking at the ball, dragging Wilmot down. And he’d been told just before the corner was taken, the referee had spoken to him,” Gallagher said.Charlton coach blames Harambee Stars midfielder after costly error in 4-0 Stoke defeatThe former Premier League official was particularly unimpressed by Ouma’s actions and made it clear that, had he been in charge of Charlton, his frustration would have been directed at the player rather than the referee.“Yeah, you’d be angry at your player, not the official. If I were the head coach, I’d be looking at my player because they’re at fault. It’s not the referee’s fault,” he added.Gallagher’s comments underlined just how avoidable he considered the incident, with Ouma not only failing to track the ball but also ignoring the referee’s warning before the set piece.The penalty set Stoke on their way and opened the floodgates, with the hosts capitalising on Charlton’s defensive struggles to secure a comprehensive victory.Harambee Stars winger breaks Alexander Isak's record after scoring first LaLiga goalEthan Galbraith doubled Stoke’s advantage inside the opening 15 minutes when he fired a low effort beyond Charlton goalkeeper Arthur Okonkwo.George Hirst then added a third, rising to head home Eric Bocat’s delivery and leave the visitors facing a daunting deficit before the break.Devenny completed his brace shortly before half-time, converting his second goal of the afternoon to send Stoke into the interval with a commanding 4-0 lead.Charlton were unable to mount a response after the restart as Stoke comfortably protected their advantage and claimed maximum points.Former Harambee Stars midfielder obtains UEFA A coaching license in BelgiumThe defeat brought Charlton’s unbeaten start to the Championship campaign to an abrupt end. The Addicks remain sixth in the table on 10 points, just one point behind leaders Swansea City despite suffering their first loss.