Sanson yesterday completed his anticipated move for Marseille, for an initial fee of £14million, penning a four-and-a-half year deal at Villa Park.
The 26-year-old will not feature in tonight’s Premier League clash at Burnley but could be involved at Southampton on Saturday.
Smith, who will put Sanson through his paces on the training field for the first time tomorrow, said: “We’ll get a good idea after his first training session of where his fitness is.
“But his numbers are really good and he’s back to fitness and playing minutes.
“He’s been playing at the top of the French league for the last five or six seasons and we know he is robust enough to cope with the demands of the Premier League.”
Sanson underwent a medical in Paris on Monday after Villa agreed a fee with Marseille which could eventually rise to £15.5m.
The former France under-21 international then travelled to the UK yesterday afternoon to formally complete the move after receiving his visa.
He will compete with Ross Barkley, Douglas Luiz, John McGinn and Marvelous Nakamba for a place in Villa’s midfield, with Smith particularly excited about his versatility.
The boss continued: “His assets are his ability on the ball to see a pass. He can create, he can break things up, he has good legs and loads of energy around the midfield area.
“He is a hybrid player as well. He can play as a 10, 8 or as a 6. He certainly gives us a lot of options in the midfield area.”