Sofia Challenger page help: Odds Portal lists all upcoming Sofia Challenger tennis matches played in Bulgaria. "B's" column indicates number of bookmakers offering Sofia Challenger betting odds on a specific tennis match. Columns 1, X and 2 serve for average/biggest Sofia Challenger betting odds offered on home team to win, draw and away team to win the Sofia Challenger match. The top line of upcoming matches table (Tennis - Bulgaria - Sofia Challenger) lets you click-through to higher categories of Odds Portal betting odds comparison service.