Poláček arrived from Czech top flight newcomers FK SIAD Most to replace Slovakian Marek Čech, who left Sparta for FC Porto on Wednesday. The 25-year-old had caught the eye in Most's opening four games of the season. However, he needs no introduction to Sparta coach Jaroslav Hřebík, who gave Poláček his First Division debut with SK Slavia Praha seven years ago.
Loučka, who rejoins Sparta from FK Jablonec 97, is another familiar face for Hřebík. The 23-year-old was a trainee at the capital club and played under the coach for Sparta's reserves. He quit the Toyota Arena two years ago to sign for SFC Opava. Both Poláček and Loučka have signed three-year contracts with the club.
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