Chelsea have concluded their Champions league group-stage campaign with a 2-1 victory over Dinamo Zagreb at Stamford Bridge, but Wednesday's match ended on a sour note as Ben Chilwell sustained a hamstring injury.
Raheem Sterling and Denis Zakaria, on debut, cancelled out Bruno Petkovic's early opener as the Blues recorded their fourth successive win in Group E and 100th success in the history of the competition.
However, in the final seconds of the game, Chilwell sustained a hamstring injury, making the England international a major doubt for the World Cup which begins later this month.
Zagreb needed to win to earn third place and a spot in the Europa League, but that never became realistic as Chelsea dominated the closing half hour with a lead intact.
As expected, Chelsea head coach Graham Potter rung the changes from Saturday's 4-1 defeat at Brighton & Hove Albion and handed a first appearance to Juventus loanee Zakaria.
Despite the Blues controlling the opening stages, it was Zagreb who went in front after just six minutes when Cesar Azpilicueta failed to deal with a cross from the right and Petkovic had the relatively simple task of firing a header past Edouard Mendy from six yards.
In response, the home side remained patient in possession, but they were soon rewarded with an equaliser when Pierre-Emerick Aubameyang cleverly back-heeled the ball into the path of Sterling, who took an extra touch before sending a low effort into the bottom corner from by the penalty spot.
Aside from the two goals, there was little sustained action in the final third, and that trend continued as the game headed towards the half-hour mark when Zakaria put Chelsea in front.
Kai Havertz bided his time on the right-hand side of the penalty area before his pass was deflected into the path of the midfielder, who swept the ball into the bottom corner via a defender standing on the line.
Zagreb again looked a threat soon after the restart, Josip Sutalo seeing a header from a corner well kept out by Mendy after the defender had beaten Kalidou Koulibaly in the air.
Chelsea went up the other end and came agonisingly close to netting a third as Aubameyang cut inside onto his right foot before seeing a curling effort strike the crossbar and rebound clear.
With Arsenal, Manchester City and Newcastle United to come before the World Cup, Potter made a triple change at the break, replacing Koulibaly, Havertz and Aubameyang with Thiago Silva, Conor Gallagher and Armando Broja.
As the game entered the final quarter, Zakaria's otherwise-positive debut ended on a low note as he hobbled off with an injury, and the intensity of the game also dropped.
Chelsea were dominating, however, and went close through Mason Mount, who saw a free kick tipped over the crossbar by Dominik Livakovic, while Gallagher was denied at the near post by the Croatia international.
The minutes continued to tick down and Silva somehow failed to convert from close range after meeting a free kick from Chilwell, before Gallagher wasted an even better opening in the six-yard box as he fired straight at Livakovic after meeting Mount's low cross.
As the minutes were ticking down in added-on time, Chilwell pulled up sharply on the left-hand side with a hamstring injury, the defender looking distraught given that Gareth Southgate names his England squad in just over a week's time.
Despite finishing the group three points clear of AC Milan, the focus will be on the injury picked up by the in-form wing-back, and he appears certain to miss the upcoming triple-header before the break.
