Napoli are still sweating on the injury sustained by forward Gonzalo Higuain in Saturday's 0-0 draw at Inter.
The Argentina striker was forced off in the closing stages of the San Siro clash after a heavy challenge from home defender Marco Andreolli.
Higuain had to be stretchered from the field and received oxygen as he appeared to be in serious pain.
Napoli confirmed the former Real Madrid man has suffered a painful impact injury to his ankle, though a timescale for his return is yet to be defined.
Rafael Benitez will be desperate for Higuain to regain his fitness as soon as possible with next week's Coppa Italia final against Fiorentina looming.
A club statement read: "Strong blunt trauma to the right tibia. This the outcome of examinations submitted this morning on Gonzalo Higuain after the collision during Inter-Napoli with Andreolli.
"Clinical tests have confirmed what was first diagnosed yesterday.
"(Higuain) today did therapy and his condition will be evaluated in the coming days."
Argentina coach Alejandro Sabella will also take a keen interest in the fitness of Higuain, who is expected to be a part of his FIFA World Cup plans.
|Coach: W. Mazzarri|
for D. D'Ambrosio 68'
for Hernanes 74'
for M. Icardi 81'
|Parejo re-signs with Valencia|
|MLS Review: Sounders return to winning ways|
|Klinsmann unhappy with USA performance|
|High hopes for Paraguay - Diaz|
|Gareca: More to come from Peru|
|Gerrard had European offers|
|Argentina out to spoil Chile´s party - Martino|
|Sampaoli: Chile won´t change style|
|Di Maria will come good at United - Rojo|
|Peru 2 Paraguay 0: Gareca´s men finish third at Copa|
|United States 4 Guatemala 0: Klinsmann´s men win comfortably|
|´I’d prefer no-one to know my name´ - Bassett|
|Matthews completes Sunderland move|
|Podolski set for Galatasaray medical|
|Gundogan inspires Dortmund victory|
|Inter confirm Montoya capture|
|Murillo joins Inter, as Kuzmanovic and Obi depart|
|Falcao signing not a risk, says former Chelsea star|
|Deeney agrees new Watford deal|
|Confidence and service the key to Falcao success at Chelsea|
|No bids for ´Chelsea target´ Baba, claim Augsburg|
|Derby swoop for Ince|
|Fiorentina consider legal action over Salah ´no-show´|
|Chelsea the team to beat in the Premier League, says Neville|
|Storari exits Juve for Cagliari|
|UEFA removes FFP restrictions on Man City and PSG|
|West Brom hope for new owners within the month|
|Chelsea agree loan deal for Falcao|
|Kuyt eyes trophies on Feyenoord return|
|Chile v Argentina: History beckons ahead of Copa America final|
|Wallace extends Monaco loan|
|Mihajlovic wants to instill fear factor at Milan|
|Mignolet improving at Liverpool - Grobbelaar|
|Mumbai City name Anelka player-manager|
|Olivia the parrot predicts Japan to win Women´s World Cup|
|Lusitans coach blasts Bilic´s ´lack of respect´|
|Sakho eyes more Europa League wins|
|Gareca wants Peru to keep building|
|Chile ´no chance´ if Argentina produce their best - Diaz|
|Ocampos joins Marseille permanently|
|Europa League Review: Cloud-nine Brondby ignite opening round|
|West Ham 3 Lusitans 0: Sakho nets twice at start of Europa League journey|
|Holebas makes Watford move|
|Milan secure Adriano signing|
|Peru v Paraguay: Diaz counts cost of semi-final loss|
|Bastia hit out at reports of extra debt|
|Hernandez has successful surgery|
|Odemwingie signs one-year Stoke extension|
|Uth signs for Hoffenheim|
|Henen seals Everton return|
|Cattermole pens long-term Sunderland deal|
|United States v Guatemala: Klinsmann backs Dempsey ahead of Gold Cup warm-up|
|West Ham working on Jenkinson return - Gold|
|Milan agree deal for Bacca|
|Real buy back Vazquez from Espanyol|
|Richards leaves Swansea for Fulham|
|McShane signs for Reading|
|Giggs tells youngsters to seize US chance|
|Hammond pens Leicester extension|
|Only Schweinsteiger can decide Bayern future - Guardiola|
|Cech plans to play until he´s 40|
|Montoya arrives in Milan ahead of Inter move|
|Hernandez out of Gold Cup|
|US asks Switzerland to extradite seven FIFA officials|
|MLS Preview: Sounders seek momentum switch|
|Mexico 0 Honduras 0: Hernandez injury sours friendly|
|Hernandez taken to hospital|
|Garay in doubt for Copa America final|
|Wambach: USA peaking for World Cup final|
|Bassett ´an absolute hero´ despite own goal - Sampson|
|Japan 2 England 1: Late own goal breaks English hearts|
|Salvo quits as Valencia president|
|Costa not Ribery cover - Bayern director Sammer|