The Spaniard was appointed interim manager in the wake of Roberto Di Matteo's dismissal by owner Roman Abramovich last week.
The Blues are lying fourth in the Premier League standings and face Leeds United in the League Cup quarter-finals.
However, they're close to elimination from the Champions League and will need to beat FC Nordsjaelland at Stamford Bridge next week and hope Shakhtar do them a huge favour and beat Juventus in Donetsk next week to reach the last 16.
Chelsea also travel to the FIFA Club World Cup in Japan in a fortnight's time, before they start their defence of the FA Cup in January.
And Zenden, who spent three seasons at Stamford Bridge after signing from Barcelona in 2001 is confident the west Londoners can do well.
"We're battling for five prizes and in December we play for the Club World Cup," Zenden told NuSport. "After that, we will see what happens.
"For me, this is a super chance to gain experience at the top level of coaching. I could never dream of it, so I'm ready to take my opportunity with both hands."
Zenden also admitted he was surprised at receiving the call by Benitez to be his number two.
"Absolutely. I met Benitez a couple of weeks ago in Doha and we exchanged numbers.
"Last Wednesday he suddenly called me and asked me to be his assistant at a top side. Some time later it turned out to be Chelsea and the next day I was already in London."