LONDON Australia showed why they are the hot favorites to win the Olympic men's hockey gold on Wednesday when they ripped apart a Spanish side visibly shaken by losing to injury a second top striker in as many games.
Later, Britain let their half-time lead slip and were lucky to draw 2-2 in a thriller against South Africa.
World Champions Australia beat Beijing runners-up Spain 5-0 in a game overshadowed by an injury to 34-year-old Pol Amat.
The Spanish striker fell over an Australian player in the 23rd minute. He was led off the field with medical staff holding his arm and taken to hospital.
The Spanish hockey federation later confirmed Amat had dislocated his shoulder and would be out for at least two to three weeks, a serious set-back to the medal ambitions of Spain who were already missing their captain.
Santi Freixa, who denied Australia a place in the Beijing final four years ago by scoring the semi-final's only goal, broke his left arm in the team's 1-1 draw against Pakistan two days earlier.
"The three games without Pol and Santi will be tough for us, but we have to play. We will have to win and reach the semifinals. We will have to," said Spanish goalkeeper Francisco Cortes after the game.
Australia had made a strong start, taking the lead with a well-placed flick by Russell Ford in the 10th minute, followed less than five minutes later by a Matthew Butturini goal from seven meters and Spain never recovered.
Despite encouragement to move forward, the Spanish side, down 3-0 at half time, kept all 11 players in their own half during most of the second 35 minutes of the game and just managed to limit Australia to two more goals.
Australia now has an impressive 11 goals from just two matches and leads Group A with six points. Britain's draw keeps them second in that group. Two teams from each group progress to the semifinals.
The hosts got off to a strong start when captain Barry Middleton - earning his 100th cap - flicked a ball just wide after a quick break in the fifth minute.
It then took Britain another nine minutes to score, when Ashley Jackson first won, then converted, a penalty corner with a classy drag flick.
But after an uneventful first 20 minutes of the second half, in which a passive-looking Britain lacked the determination to close out the match, South Africa's game plan of interrupting the hosts' play worked for them.
Ten minutes before the end, South Africa captain Austin Smith converted a penalty corner with a drag flick that skillfully dipped at the end of its flight. Four minutes later Jonathan Robinson hammered the ball into goal past three British defenders, putting South Africa into the lead.
A wake-up call for the crowd and the British team, the hosts then rallied back and with just under three minutes left, Britain substituted their goalie for an additional field player to score a disputed equalizer three seconds later.
A pass out of midfield from Richard Smith into the circle was deflected into goal but looked like it had come off a foot or South African stick, not touched by a British stick within the shooting area, which is a requirement for a hockey goal.
But after the umpire called a video referral, the equalizer goal was allowed and awarded to Ashley Jackson.
"After this performance, I'm pleased with the result and see it as one point gained as opposed to three lost (if Britain had not equalized). We struggled with South Africa's attitude," said British coach Jason Lee.
(Additional reporting by Iain Rogers in Madrid, Editing by Nigel Hunt)