They hit their heads together when heading the ball.

争顶头球时，二人的头撞在了一起。

youdao

All I know is he was heading the ball and an Arsenal player tried to protect his goal and accidentally kicked JT in the head.

我所知道的就是他在头球攻门的时候被解围的阿森纳球员一脚踢中面部。

youdao

Since we still can't detect any sign of brain damage, we can say that heading the ball is not dangerous, "says Henrik Zetterberg."

但我们还是不能检测到任何的大脑损伤的迹象，所以我们可以说头球并不危险。

youdao

In the ninth inning, Tampa Bay batter Gabe Kapler sent a ball heading for the stands in left-centerfield, threatening a home run and spoiling Buerhle's perfect game.

VOA: standard.2009.07.24

Four minutes into stoppage time, Harris netted his second goal when heading the ball home following a cross from veteran fellow frontman Steve Claridge.

BBC: Millwall 3-0 Derby

That initial spurt of pressure saw Liverpool win a corner with Maxi Rodriguez heading the ball to Torres, but the Spanish striker's volley struck the post.

BBC: Wigan 1-0 Liverpool

Spurs argued at the award of a Chelsea corner as they believed Joe Cole was offside when Essien took his shot prior to Jonathan Woodgate heading the ball out.

BBC: Chelsea 1-1 Tottenham