Inter Milan striker Pablo Daniel Osvaldo faces a race against time to be fit for the Milan derby on Nov. 23 after tearing his adductor muscle while on international duty.
Osvaldo, 28, has been ruled out for at least a month after picking up the injury towards the end of Italy's final training session on Thursday ahead of their game against Azerbaijan.
The former Southampton forward is set to miss seven games for the Nerazzurri after making an impressive start to the season, scoring twice in the 7-0 win over Sassuolo.
He was ruled out of the Italy squad in September with a hip injury and once again misses out on national team duty this month.
Osvaldo also now seems certain to miss Italy's next appointments in November, including a crucial Euro 2016 qualifier against Croatia at the San Siro.
His absence also leaves Inter coach Walter Mazzarri with a predicament ahead of a testing fixture with his former club Napoli.
He only has Mauro Icardi and Rodrigo Palacio available, unless he opts for one of his club's youth team forwards.
George Puscas, 18, has scored 10 goals in four games for the Inter youth team while Federico Bonazzoli, 17, has scored five in three.
Both have already spent time training with the first team this season and, with Osvaldo set to miss so many games -- including the double-header with Saint-Etienne in the Europa League and home games against high-flying Sampdoria and Hellas Verona -- they may be blooded sooner than planned.
Icardi and Palacio may struggle to hold the fort between them for such a hectic schedule of matches. While the latter has started only twice this season, coming on as a substitute three times, Icardi has played six and scored three.
The other option could be Fredy Guarin, who missed Inter's last game against Fiorentina due to injury but was nevertheless called up to the Colombia national team for friendlies against El Salvador and Canada.
Inter will be hoping he does not aggravate that injury while on international duty, or Mazzarri's options really will be limited for a game his side need to win.
With just two wins in six, Inter are already three points adrift of the top five and two behind opponents Napoli.