Michael Bradley, wounded after head-to-head collision with Davy Arnaud at BMO Field on Saturday. (By Tom Szczerbowski -- USA TODAY Sports) Michael Bradley, wounded after head-to-head collision with Davy Arnaud at BMO Field on Saturday. (By Tom Szczerbowski — USA TODAY Sports)

D.C. United’s Davy Arnaud did not suffer a concussion in a frightening head-to-head collision with Toronto FC’s Michael Bradley on Saturday but was held out of practice Tuesday for further observation, Coach Ben Olsen said.

“We want to make sure he’s okay and check him out because it was a pretty nasty hit,” Olsen said.

Arnaud received nine stitches above the left eye after departing in the 64th minute. (Because of the location of the wound, he could not continue.) Bradley was bandaged to stop bleeding to the back-top of his head and returned to the game. He later received 13 stitches.

Afterward, Bradley sought out Arnaud in the locker room to see if he was okay, a class gesture by the U.S. national team midfielder.

However, MLS’s disciplinary committee will take a hard look at the sequence — as it does with all plays that result in injury.

As one United player told me: “Michael wasn’t going to win the ball.” Olsen did not want to comment on the incident. Arnaud was not available for interviews after the match or Tuesday. [Click here to watch SB Nation’s gif of the play.]

“We’re glad he’s okay,” midfielder Luis Silva said. “That was scary. [Later,] he looked like a boxer” with stitches and swelling.

Said D.C.’s Eddie Johnson, Bradley’s U.S. teammate: “I don’t think he did it intentionally, but I think it was a little late. Michael is not a dirty player, Davy is not a dirty player.”

The Toronto TV analyst said this during the broadcast:

“There is no need for Bradley to go into this challenge — he is never going to win this ball. Arnaud was always favored to get there first and comes off worst for wear.”

In an era of greater awareness about head injuries and concussions, is a suspension in order? The league would announce any such penalties late in the week.

It was a rough 24 hours for Arnaud: On Friday, he arrived at RFK Stadium with an eye infection and had to see a specialist, forcing him to miss training. Early in the second half, Arnaud was elbowed in the ribs by Toronto’s Jackson. As Bradley prepared to serve a free kick, players were jostling for position at the top of the penalty area. Arnaud chest-bumped Jackson from behind. Jackson retaliated with a right elbow. The Toronto winger received a yellow card. [Several replays of the incident are available in this video.]

In Toronto’s opener, Jackson was lucky to dodge a red card when he took down Seattle’s Clint Dempsey from behind in the sixth minute.

UPDATE: Jackson has been suspended one game, pending a possible appeal, the Insider learned late Monday.

Arnaud’s status for this Saturday’s match against the Chicago Fire at RFK Stadium (4 p.m., NBC Sports Network) will be determined later in the week.