(CNN) -- Germany coach Joachim Low has suffered another injury blow ahead of the World Cup, with captain Michael Ballack's possible replacement Christian Trasch also ruled out.
Trasch had been touted to go to South Africa, with Germany short of experienced midfielders after Bayer Leverkusen's Simon Rolfes and then Ballack were sidelined, but the 22-year-old sprained his ankle early in a practice match in northern Italy on Monday night.
"Christian Trasch will not be available for us at the World Cup. It's disappointing news as Christian would have been in our final squad," assistant coach Hans-Dieter Flick told the German Football Association Web site on Tuesday.
Low will not replace Trasch in his provisional squad, which he now needs to trim by two players to 23 by the June 1 deadline.
Bayern Munich's 74-cap Bastian Schweinsteiger is now Germany's most senior midfielder, with Hamburg's Piotr Trochowski, gifted playmaker Mesut Ozil and the left-sided Marko Marin also vying for places along with Trasch's two-cap Stuttgart clubmate Sami Khedira and 20-year-old Toni Kroos.
Ballack was ruled out of the World Cup after suffering an ankle injury in the English FA Cup final earlier this month.
The Chelsea midfielder was caught by a bad tackle from Portsmouth's Berlin-born Kevin-Prince Boateng, who has decided to switch nationalities to play for Group D opponents Ghana and whose half-brother Jerome was earlier named in the preliminary 27-man German squad.
With No. 1 goalkeeper Rene Adler also sidelined by injury, the 35-year-old Hans-Jorg Butt received his first call-up since 2003 to vie for a starting place with Schalke's Manuel Neuer and Werder Bremen's Tim Wiese.
Butt's young Bayern Munich clubmates Holger Badstuber, 21, and Thomas Muller, 20, gave the Bundesliga champions seven players in coach Joachim Low's squad.
