Cole Palmer barely hid his frustration as he was a casualty of Chelsea boss Enzo Maresca’s enforced first-half tinkering.Palmer was taken off in the 21st minute of the Blues’ clash against Manchester United at Old Trafford, with Andrey Santos replacing him. As Palmer trudged off the pitch and was met by Maresca, he tossed his gloves off to the side.The England international was then captured in an oversized coat walking down the sideline.Palmer even stopped for a brief chat with Red Devils sub Kobbie Mainoo before he made his way up the tunnel at Old Trafford.He eventually returned to the visitors’ dugout later in the first half.Why did Chelsea make so many substitutions?In what could be a worrying sign, Palmer appeared to point to his groin as he came off, meaning his early departure may have been injury-related.Palmer was one of three early substitutions for Chelsea as a result of goalkeeper Robert Sanchez’s red card.It forced Maresca to take off young forward Estevao so back-up goalkeeper Filip Jorgensen could enter the contest.Maresca also beefed up his defence as winger Pedro Neto came off for centre-back Tosin Adarabioyo.The three substitutions from the visitors was the first time in Premier League history that a team had made that many changes inside 21 minutes.Unfortunately for Maresca, his substitutions didn’t quite have the desired effect.Palmer wasn’t best pleased about being hooked earlyJust seven minutes after Jorgensen and Adarabioyo’s arrivals, the Blues were behind courtesy of United skipper Bruno Fernandes’ goal.Fernandes was on hand to poke home Patrick Dorgu’s header and although a lengthy VAR check ensued to determine whether the Portuguese international was offside, the goal stood.Chelsea’s evening went from bad to worse in the 37th minute when Casemiro doubled United’s advantage.Once again Dorgu was key in the build-up as his header forced Blues skipper Reece James into a poor clearance that sailed high into the air.United defender Harry Maguire then got a decisive touch onto the ball and it fell kindly into the path of Casemiro, who made no mistake from just in front of goal.However, the Brazilian midfielder quickly went from hero to villain when he picked up his second yellow card of the contest just before half-time.More to follow…