Sparta originally wanted Petrouš three years ago, when he was with SK Slavia Praha, but their city rivals refused to sell him. However, the 27-year-old now joins the Czech champions from Russian side Rubin, where he had played since November 2003.
Petrouš, a silver medallist with the Czech Republic at the 2000 UEFA European Under-21 Championship, failed to settle in Russia and played on loan at FK Austria Wien this spring.
Sparta had already strengthened their defence with the capture of Petr Lukáš from FC Slovan Liberec and Zdeněk Pospěch from FC Baník Ostrava, in addition to signing Liberec's Slovakian midfielder Karol Kisel. Amid the incomings, stopper Petr Johana has left the Toyota Arena for trials in Turkey.
©UEFA.com 1998-2016. All rights reserved.