Former crystal Palace manager Frank de Boer was a pundit on Saturday speaking on BT Sport's Premier League Tonight said 'it's a pity' Manchester United forward Marcus Rashford plays under manager Jose Mourinho. The Manchester United youngster Marcus Rashford scored twice in Manchester United's 2-1 win over rivals Liverpool on Saturday in what was a rare start for the 20-year-old. Rashford has started 14 games out of his 27 Premier league appearances this campaign and has scored 12 goals in 40 appearances for the Red Devils in all competition this season. The match against Liverpool gave Marcus Rashford his first start of the year in the Premier League and his brace in the game were his first goals of the news year has he has struggled to make the squad. The signing of Belgium striker Romelu Lukaku forced Rashford to be deployed to the wings and he's been fizzled out of the starting line up since the signing of Alexis Sanchez. Injury to play maker Paul Pogba gave the English man the opportunity to feature in the starting line up and that was an opportunity he did not take for granted. Former Crystal Palace and Ajax boss De Boer does not believe Mourinho has the patience to allow Rashford the necessary room to develop and that the pressure on Mourinho to get results is hampering Rashford’s progress: "It's a pity that the manager is Mourinho, because he's an English player and you want him to be given time, He can make mistakes but Mourinho is not like that and if he has one or two not good games then he puts him out. "He's very young, he needs games. But he's so talented and you want to see him play every week. De Boer said on BT Sport's Premier League Tonight. Mourinho was obviously irated by De Boer’s comments, and has labelled ex-Netherlands star "worst manager in the history of the Premier League." The former Ajax boss was shown the exit door at Crystal Palace where he was in charge of just five competitive matches as Crystal Palace boss earlier this season, losing all his four games in the Premier League without managing a goal but beating Ipswich in the EFL Cup before his dismissal on September 11 after just 77 days in charge. Ahead of Manchester United’s match against Sevilla in the Champions League Mourinho said: ‘I read something, some quote from the worst manager in the history of the Premier League, Frank de Boer who played seven matches, recorded seven defeats, and recorded zero goals, saying it’s not good for Rashford to have a coach like me because the most important thing for me is to win. ‘If he was coached by Frank he would be coached how to lose because he lost every game. I try to give the best to the kids, education. Marcus I have to be honest and give the credit to the people of the academy that were responsible for his formation and to Van Gaal for his first season in the first team. If you go to his numbers and how many games he played with me. I would say he was in the top five with more matches for two season. Most United fans have jumped to the defence of Jose Mourinho but truth be told, Frank De Boer was on point. Rashford has not been able to maintain the momentum with which he started at Old Trafford under Louis Van Gaal. The 20 year-old scored five goals in 11 EPL matches in 2015-16 his breakthrough season but after Mourinho took over the following season, he scored the same number of goals in 32 games and has now scored six times league goals this season playing mostly as a substitute. Related articles The father of tactics, José Mourinho. Mourinho second spell at Chelsea, a curse for the London club Rooney reveals why Mkhitaryan who failed at United will excel at Arsenal. Mourinho concedes title to Man City but believes he can win the title next season. Adebayor: Mourinho is the most honest coach I've worked with unlike fake Arsene Wenger Mourinho's clarity of his vision for where he wants his sides to get to is often as clear-sighted as it is prescient and as De Boer said Rashford is unlucky to have a coach like Mourinho whose main objective is to win. We saw how he handled Mohamed Salah, Kevin De bruyne and Romelu Lukaku. it was the lack of playing time that was the key factor in all three leaving when he was with them at Chelsea. Mourinho name should be mud for allowing the three players leave Chelsea infact, young players don't get run of games to prove themselves under Mourinho. Take Anthony Martial, Jesse Lingard and Marcus Rashford as case study they have seen less of playing time. How do they get to develop when they see less of playing time? And why will Mourinho go for Sanchez when you have all these players? That's because you don't believe in them. No matter what, I still believe Frank De Boer has a point, Rashford would have developed faster if he has a coach like Allegri, Zidane or Pep Guardiola. What do you think? Have a say, drop your comments below.