The giant former AZ Alkmaar goalkeeper arrived at Spurs Lodge for a trial period on Monday.
"Oscar is very experienced," said Hans. "He's been playing at AZ Alkmaar where he's been first-choice goalkeeper for a number of years, I think he's played over 250 games for them. He's played twice for Holland as well.
"That experience is what we're looking for, just in case something happens to Kasey, at least here is someone who can do a job.
"I haven't seen him for a couple of years so we'll take a look at him and see how he is."
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As coach Hans stressed, Rob Burch's inexperience at senior level, the departure of Neil Sullivan to Chelsea and injury to Shwan Jalal has left us with just three senior goalkeepers.
"Shwan will be out for about six months," he revealed. "He's injured his cruciate ligaments in his knee so all of a sudden we've only got three goalkeepers and for a team like Tottenham Hotspur, we need one more just in case.
"Burchy has done very well and I'm sure he'd be okay for two or three matches in the Premier League but put him in for two months and he hasn't got that experience - it's a different world between reserves and the Premier League. This is to cover ourselves."
Hans Segers has explained that the need to cover Kasey Keller is why we're taking a close look at Dutch keeper Oscar Moens.