Challenger Vault: Sascha Zverev May 23, 2018 In this edition of the Challenger Vault, Alexander Zverev reflects on the title that moved him into the Top 100, when he prevailed on home soil in Heilbronn, Germany, in 2015. Tags: 2018 Alexander Zverev Challenger Heilbronn Share 0 Share on Facebook Tweet Tweet on Twitter +1 +1 on Google Plus