PHOENIX -- A bunt led to a brawl in the World Baseball Classic on Saturday, with players from Mexico and Canada exchanging blows in a melee that resulted in seven ejections and a call for changes in the tournament’s rules.

“That’s not the way baseball is supposed to be played,” Team Canada manager Ernie Whitt said following his team’s 10-3 victory that turned violent at the end.

It’s not the way it’s normally played, that’s for sure.

But in a round-robin tournament in which every run is significant — the more the merrier — matters got out of hand in the top of the ninth inning at Chase Field when Canada’s Chris Robinson, with his team leading 9-3, dropped down a bunt single to open the inning.

Under normal circumstances, Robinson’s bunt would be considered a serious breach of etiquette and not attempted out of professional courtesy. But the WBC rules are different.

Run differential is the first tiebreaker when two teams have the same record, and with only two of the four countries in each pool advancing to the next round, chances are good it will come down to that.

As a result, piling it on is not only permitted in the WBC, it’s advised.

“In this tournament, you play baseball like it’s 0-0,” Whitt said. “You play it like a 0-0 game the whole time.”

Even before the ninth, Saturday’s contest had been chippy.

Canada’s Rene Tosoni had upended Mexico shortstop Gil Velazquez with a hard slide into second, and Karim Garcia had bulled over Robinson, the Canadian catcher, on a play at the plate. Robinson, who had been hit in the groin with a foul ball on the previous pitch, applied the tag.

“It was just unfortunate that it was the pitch after getting hit in the [genitals], Robinson said. “I hadn’t even caught my breath yet, so I was talking in my soprano voice.”

But the game really turned physical in the ninth.

Mexico didn’t take kindly to Robinson’s bunt, seeing it as a sign of disrespect, rather than a strategical decision, and went after Canada’s next hitter, Tosoni. Replays showed Mexico third baseman Luis Cruz motioning to pitcher Arnold Leon and pointing to his ribs.

The message, in other words: take aim on Tosoni.

Cruz missed with two inside pitches near Tosoni’s knee, resulting in a warning to both benches by home plate umpire Brian Gorman. The warning did not dissuade Leon, though, and he drilled Tosoni in the back with the next pitch.

Benches cleared immediately, and the situation deteriorated quickly.

Unlike most baseball skirmishes, tempers in Saturday’s disagreement resulted in fisticuffs, as a huge throng of players for both teams congregated at home plate and began throwing punches, hauling each other to the ground, and putting their opponents in headlocks.

“It’s part of the game that you don’t see all the time,” Canada first baseman Justin Morneau said. “Usually it’s just words being said. There’s not always punches being thrown. But there’s a point you’ve got to stand up for yourself.”

The turmoil spilled over into the stands.

A bottle was thrown from behind the Canada’s dugout that struck their pitching coach Denis Boucher in the face. Later, after order was restored and the game resumed, a fan threw a ball onto the field that nearly hit Larry Walker, Canada’s first-base coach.