Who was the old man?

[The Might]

Keep in mind alatar, that many of the new abilities that Saruman may have had were unknown to Gandalf.
Saruman was well learned in the lore of the rings and had forget a ring of power of his own, indeed of lesser power, but still - who knows what he could achieve with it?

A very very interesting thing I just found out is this:

'He wore a ring on his finger. [...] For Saruman the White is, as some of you know, the greatest of my craft, and was the leader in the White Council.... But Saruman long studied the arts of the Enemy, and was thus often able to defeat him; and the lore of rings was one of his chief studies. He knew much of the history [of the rings of power >] of the Nine Rings and the Seven, and somewhat even of the Three and the One; and it was at one time rumoured that he had come near the secret of their making. ~ HOME7

If he had indeed come close to the secret of the making of the Rings of Power, that shows his Ring wasn't that weak at all... so why not believe he could conjure up phantoms unknown to Gandalf.

Unfortunately no clear examples of him doing so are known or at least I recall none.