Liverpool legend Toshack reckons the Kop chief's constant tinkering is angering the fans and testing the patience of the club's top brass.
He said: "I really hope Rafa knows what he's doing, as it's clear people at Liverpool are starting to get a bit nervous.
"Having spent a very significant amount of money on around 40 players in just over three years, I hope Rafa hasn't bitten off more than he can chew.
"The evident danger is that, with so many footballers now in the first-team squad at Liverpool, it's very tough indeed to keep everyone sufficiently happy.
"But, more importantly, it's the case that if you change the team so regularly then the players simply don't have time to gel together on the pitch."
The Reds' current form of only one win in their last six Premier and Champions League matches is not what the supporters want to see.
And Toshack added: "I guess by now Rafa must even be beginning to doubt the truth of the Liverpool anthem 'You'll Never Walk Alone'.
"Two of his closest assistants, Pako Ayestaran and Jose Ochotorena, have left and things are not as they once were for him.
"Time will be the judge of what is happening right now."