The Irish striker was away on holiday when Postiga checked in at the Lane and had just returned for pre-season when the Zamora deal was clinched.
He admits that he was keeping tabs on the transfer market while he was away and is happy that the striking department has been supplemented.
"Of course, you hear things and it is an exciting time for the club," said Robbie, who backs Zamora to bridge the gap between Nationwide and Premiership football.
"He is a good player and he has proved in the divisions below that he can score goals - and has proved it again here in pre-season.
"Hopefully he can make the step up to the Premiership. He is a quality player, he's young and is a good talent."
Robbie was not about to be completely outdone by the former Brighton striker at Oxford on Sunday and marked his return with a top corner special.
"Yeah - not bad! It was just one of those that I connected nicely with and luckily enough for me it went in the back of the net.
"It's nice to be back and it's always nice to score a goal. It is good to have a break, but I like to get back and get amongst it again.
"The lads have been back a couple of weeks and for me, Stephen and Doc it has only been four days. It is important that you get the rest as well because it was a long season on top of the World Cup and this year my season didn't finish until the 11th of June.
"You need your time off and I feel good. It is always nice to score goals in pre-season but the most important thing is to get your fitness for the start of the season because you don't get points from these games."
Robbie Keane says that the double capture of Helder Postiga and Bobby Zamora signals an exciting time for the club.