PHILADELPHIA -- Mykhailo Mudryk scored his first Chelsea goal and Christopher Nkunku continued his promising preseason form as the Blues secured a 4-3 win over 10-man Brighton in Philadelphia on Saturday.

Brighton took a 13th-minute lead through Danny Welbeck before Chelsea equalised courtesy of Nkunku's second strike in as many matches on their United States tour.

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This entertaining game was in the balance until Jan Paul van Hecke was sent off on the hour mark for a reckless second bookable offence and Chelsea capitalised on their numerical advantage with three goals in 11 minutes as Mudryk, Conor Gallagher and Nicolas Jackson all found the net.

Brighton rallied as João Pedro converted a 79th-minute penalty before fellow substitute Deniz Undav scored a minute from normal time but Chelsea held on for their second consecutive victory under new manager Mauricio Pochettino in front of 65,128 fans at Lincoln Financial Field.

The Argentine made seven changes to the team that beat Wrexham 5-0 in North Carolina on Saturday with senior players Kepa Arrizabalaga, Thiago Silva, Raheem Sterling and Ben Chilwell coming into the lineup while Nkunku started for the first time following his £52 million move from RB Leipzig.

Brighton looked the more purposeful in possession early on and took the lead with a clever move on 13 minutes as former Blues midfielder Billy Gilmour crossed to the far post where Kaoru Mitoma headed the ball back into the path of Welbeck, who finished off the underside of the crossbar from eight yards out.

Chelsea needed just six minute to respond. Chilwell fed the ball into Carney Chukwuemeka, who exchanged a quick one-two with Ian Maatsen.

Chukwuemeka then tried to cross but his effort ricocheted off Gilmour, falling perfectly for Nkunku to steer home a simple finish from close range. That was Chelsea's only shot on target in the first half and Pochettino responded with four changes at the interval as Mudryk, Marc Cucurella, Cesare Casadei and Trevoh Chalobah replaced Silva, Chilwell, Chukwuemeka and Maatsen.

Brighton also made four substitutions with the lively Mahmoud Dahoud among those replaced but they continued to look the more threatening with Welbeck having a shot blocked by Gallagher inside the box shortly after the restart.

The game took a twist on the hour mark when van Hecke was sent off for a second bookable offence. Red cards are a rarity in preseason but referee Robert Jones had little option given the Dutchman scythed down Casadei on the touchline.

Mudryk helped Chelsea take full advantage. Driving infield from the left, he twice exchanged passes with Jackson -- introduced as a substitute moments earlier -- before firing home a low finish from the edge of the box.

Jackson registered another assist when poking a loose ball in the box through to Gallagher to convert a third on 72 minutes.

The Senegal striker, a £32m summer signing from Villarreal, then collected Cucurella's through ball to steer a shot high into the net for his first Chelsea goal.

Levi Colwill, who is a transfer target for Brighton after spending last season on loan with Roberto De Zerbi's side, then fouled substitute Pedro in the box and the Brazilian forward converted the resulting spot-kick.

Brighton continued to push forward and, with Chelsea's defence in a shambolic state, Pedro found Undav in the 89th minute and the German steered an effort past Arrizabalaga.

Nkunku's sharpness in front of goal, Andrey Santos looking bright in midfield, Mudryk's excellent strike and Jackson's intelligent link-up play were all positives Pochettino will take as Chelsea continue their Premier League Summer Series campaign against Newcastle United in Atlanta on Wednesday.