Defoe's return gives Villas-Boas a welcome selection headache ahead of Saturday's trip to Wigan.
"Yes, it's a big decision (to choose between Defoe and Adebayor), but we are extremely happy," Villas-Boas said. "It's very important for us to have Jermain back, particularly because he found the back of the net.
"Goalkeepers have been making impossible saves against him and he finally got the ball in the net the other day with a tremendous goal that helped us get the three points.
"It's good because he had a blip in terms of goals, not performances - he was always sharp - but he had a couple of injuries.
"Now he is back he gives us that quality and confidence by scoring."