Borussia Dortmund defender Mats Hummels has been banned for one Bundesliga match over a red card offence, the club said on Tuesday. Hummels was sent off in the 15th minute of Saturday’s 3-2 home defeat against RB Leipzig for a last-man foul against Leipzig’s Lois Openda. He will miss Saturday’s game at Augsburg but is eligible again for the final game of the year next week Tuesday against Mainz. Hummels said on social media he was to blame for the defeat against Leipzig because of the red card, with Dortmund in fifth now 11 points off the top in the league. The red card only affects the domest…