Christian Pulisic was withdrawn from the Chelsea starting XI to face Burnley after he sustained an injury in the pre-match warm-up.
Timo Werner took the 22-year-old winger's place in the team and scored a 70th-minute goal as Chelsea cruised to a 3-0 win after Hakim Ziyech and Kurt Zouma also scored.
Pulisic missed Chelsea's first three Premier League games of the season due to a hamstring injury, but was included in the first 11 for the draws against Southampton, Sevilla and Manchester United.
The U.S. international was brought on in the second half of the Blues' 4-0 win at Russian side Krasnodar in the Champions League in midweek and netted the final goal of the game in stoppage time.
Following the match against Burnley, Chelsea head coach Frank Lampard indicated that Pulisic's hamstring was again a concern, though he expressed optimism that the injury wasn't serious.
"He felt something on his hamstring," Lampard told the BBC. "We tried to manage him in midweek, but we’ll see what happens in the next 24 hours. We’re talking minor, nothing serious."
Later in his press conference, though, Lampard did indicate that Pulisic was frustrated and would need a scan on his hamstring.
"Christian had a small sensation in his hamstring, so we had to pull him," Lampard said. "He couldn’t play the game and he felt that in part of the warm-up.
"We will have to scan it, he is frustrated as he got fit and we rested him in the week where he comes on and scores. He is so keen to do well for us but we have to scan him and see how it is so I can’t give you a time on that."
With the victory on Saturday, Chelsea moved up to fourth in the league table, while Burnley remain rock-bottom with just one point from their opening six league fixtures.
Ziyech has now scored on his first two starts for Chelsea, becoming the first Blues player to pull off the feat since Diego Costa in 2014.
Next up for Chelsea is a Champions League clash with Rennes on Wednesday before they are back in Premier League action next weekend with a match against Sheffield United.