The fledgling Formula E racing series has received a major investment from Wyc Grousbeck, the largest single shareholder in the Boston Celtics NBA basketball team, and his company Causeway Media Partners. The investment comes to $21 million, according to the Associated Press.

“I am happy to announce that Causeway Media Partners has brought its deep network of NBA and NFL owners, as well as media executives and renowned investors, to Formula E. We believe Formula E is a great evolutionary step in motorsport and a way to entertain millions around the world while driving the development of the best possible electric vehicles,” said Grousbeck.

In addition to an undisclosed stake in Formula E, Grousbeck will gain a seat on the board of directors at Formula E Holdings, the series’ promoter.

Formula E will begin its inaugural 10-race calendar in September 2014 with a field of 10, two-car teams.