Miroslav Klose is a doubt for this weekend’s Rome derby as the Lazio man struggles with a knee problem.The forward, currently away on international duty, missed Germany’s 3-1 win in Turkey on Friday and is a concern for Tuesday’s Belgium clash.The summer signing from Bayern Munich has been suffering with a knee problem since the win over Fiorentina before the international break.Lazio will assess the veteran’s condition on his return to Rome before a decision is made on his use or not.Klose has been a sensation at the Stadio Olimpico so far this season after scoring five goals in seven appearances. Three of those strikes have come in Serie A.