Leaders Bayer Leverkusen defeated 10-man Union Berlin 1-0 on Saturday and could claim their first-ever Bundesliga title next weekend at home against Werder Bremen. Florian Wirtz scored the winner shortly before the break to give Leverkusen a 16-point advantage over second-placed Bayern Munich, who were up 2-0 but conceded a shocking 3-2 defeat to promoted Heindeinhem. “My plan was (to win the title) a bit later. The situation is very good for us now and maybe we can celebrate something on Sunday. But before that there is the Europa League and that is where all the focus lies,” coach Xabi Alons…