Three things we learned from Chelsea win as more new signings impress

Chelsea made routine work of League One side Luton to progress into the Carabao Cup third round.Leeds will now travel to Stamford Bridge next month in the latest clash between old rivals.Latest Chelsea debutants impressPenders’ distribution, at least, was promising, but the performances of Welbeck and Valentin Barco stood out.Welbeck produced a smart give-and-go with Morgan Rogers in the first half, and then latched on well to head in from Malo Gusto’s first-time cross after the interval. It was just the start the veteran signing from Brighton will have wanted.And Barco was a real force in midfield, defying his short and slim frame by physically dominating in the middle of the park, disrupting play with tackles - including a decisive interception that led directly to Chelsea’s second goal.Pedro Neto and Cole Palmer both went over to congratulate the Argentine’s smart contribution.Debut to remember: Danny Welbeck celebrates scoring his first Chelsea goal against LutonGettyChelsea attack continues to purrWhile childhood friends Rogers and Palmer both failed to get on the scoresheet, they came mightily close and were probing all evening.Rogers was as involved in Chelsea’s build-up play as anyone, jinking between three defenders at one point and, shortly after, rattling the crossbar.His England team-mate, meanwhile, toyed with Luton’s players, hinting at going one way before dragging the ball back and then darting off in the other direction. He, too, hit the woodwork, picking up a loose ball with a sweeping, curling effort which nicked off the top of the bar.It was surprising that Palmer stayed on for the full 90 minutes, but perhaps Xabi Alonso is trying to get his attack up to speed. Even without goals, Palmer and Rogers had a very noticeable influence at Stamford Bridge.Double trouble: Long-time friends Cole Palmer and Morgan Rogers have an instant connectionGettyChelsea handed new punishmentChelsea were the victims of a new rule against Luton, though it was their own fault really.Alonso was replacing Welbeck with Joao Pedro on 71 minutes, but as Welbeck took in the adulation from the home crowd, he was informed by the referee that he had taken too long to leave the pitch.Due to the new ‘Time-Limited Substitution Protocol’, Chelsea were told that Joao Pedro would have to wait at least a minute before coming on, meaning they would briefly play with 10 men.In the end it was two minutes before Joao Pedro took the field. By the time he did, there were plenty of Chelsea fans booing. But this was a positive night overall for the Blues.