Holland and Australia both clinched their places in the semi finals after the Dutch defeated Argentina 4-2 and the Kookaburras beat South Africa 3-2 in a hard fought contest.
Aiming to complete a hat-trick of titles, Holland strolled to victory over Argentina taking a 3-0 lead at the break. The Pan American champions did breach the Dutch twice in the second period but their lively temperament was to prove their downfall as they finished the match with ten players after Matias Paredes and Rodrigo Vila were both sent to the sin bin.
There was no shortage of incidents in the contest between South Africa and Australia with Protea defender Iain Evans becoming the first player in the tournament to be shown a red card after receiving two yellows for deliberate stick obstructions.
The Kookaburras took full advantage of his absence after Michael Brennan scored the winner. Putting up spirited resistance and continuing to press forward, South Africa put enough pressure on Australia for their captain Matthew Wells to also be shown a yellow card for a crude tackle on Emile Smith.
In Pool A and in the battle between the two former Dutch coaches, Roelant Oltmans (Pakistan) and Maurits Hendriks (Spain), it was Hendriks who prevailed after Eduard Tubau turned in a scintillating display of finishing scoring a hat-trick in a convincing win.
The only criticism of an almost flawless performance by Spain was their inability to score from seven penalty corners. Their solid defence was only called in to action in the closing stages to defend a corner from Pakistan danger man Sohail Abbas but he sent it wise. It was a disappointing scoreline for the Pakistan side who worked tremendously hard throughout the contest but they were outplayed in the midfield.
The result helped Spain move up in to second spot behind Germany who could afford the luxury of missing a first half penalty stroke in a dominant win against Great Britain. If Spain's finishing was clinical, so too was Germany's with their strikers also looking in ominous good form.
Michael Brennan (Australia)
"We proved we can make it through when it's tough. Even though we didn't play our best we achieved our goal to reach the semi finals and we will try to keep it up, getting the best outcome possible."
Craig Jackson (South Africa captain)
"We are disappointed. Even though we are always take the lead we end up losing. Playing in the Olympics has been a very good lesson for us. We enjoy the fact that we are here but wish we had a few more points because on the back of our performances we deserve better. From now on we will do our best to finish as high up the rankings as we can."
Jeroen Delmee (Dutch captain)
"We changed our tactics for this match, going back to a half press and keeping everything much more compact. It was much more like Holland used to play and what we are happy with."
Eduard Tubau (Spain)
"We've worked for years to achieve this level and didn't relax at all."
Josep Sanchez (Spain).
"It was a magnificent match and the result we expected. There has been a major change in Spanish hockey over the last five years and I think we're now among the top four or five sides in the world."
Maurits Hendriks (Spain coach)
"Roelant brought me in as his assistant coach when no-body else believed I should be there. From that has developed a friendship and respect."
We have changed the way the Spanish eat, sleep and practice."
Bernhard Peters (Germany coach)
"Finally we played the hockey again that we can play. It was a huge relief, technically we played brilliantly.
On Christoph Zeller: "His body and his mind is one of a 25 year old it's amazing to think he's only 19."
