Enzo Fernandez was booed by sections of the Chelsea support as he came on in the 62nd minute of a 3-1 win against Real Sociedad.
The Argentine midfielder had been the subject of intense transfer speculation in the summer, with Real Madrid and Manchester City both reportedly interested in signing him. However, Chelsea held firm and the 22-year-old remained at Stamford Bridge, albeit with a few fans unhappy with his perceived disloyalty.
Fernandez's representatives had held talks with Manchester City before Chelsea's self-imposed transfer deadline had passed on Friday at 17:00 BST, but no offer was made to meet the club's £120m valuation. The midfielder had been keen to join Real Madrid earlier in the summer, but the Spanish club ended their interest.
The action on the pitch, however, was overshadowed by the reaction to Fernandez's second-half appearance. Joao Pedro continued his fine pre-season form with a double, heading Chelsea back in front in the 47th minute before adding a side-footed finish 30 minutes later to seal victory after Sociedad had equalised just before half-time through Jon Mikel Aramburu's volley.
Morgan Rogers scored on his first appearance for Chelsea, reacting quickest after Alex Remiro saved Joao Pedro's initial header. The £117m club-record signing from Aston Villa initially looked sharp and linked well with Cole Palmer and Pedro in Chelsea's front three, with supporters already chanting his name within 10 minutes of his debut.
The 3-4-2-1 formation used by manager Xabi Alonso offered a glimpse of what could be his blueprint for the season. The system, which featured Robert Sanchez as the first-choice goalkeeper, with Wesley Fofana, new signing Maxence Lacroix and Levi Colwill forming a back three, was also used in Chelsea's 3-0 win against AC Milan a week ago.
Chelsea still have 40 senior professionals on their books, so Alonso was forced to leave out a host of players, including Nicolas Jackson, Liam Delap, Mykhailo Mudryk, Tosin Adarabioyo and Mamadou Sarr. These players are either available for transfer or attracting loan or permanent interest, with Mudryk and Sarr targeting Premier League loan moves, Jackson available for £65m, and Delap for £50m.
The reaction to Fernandez's appearance will be an issue that will remain, whether he remains at Chelsea or Manchester City elect to revive their interest and attempt to reunite him with his former manager Enzo Maresca before deadline day on 1 September.
Source: BBC Sports
