Back after a neck injury kept him out of our first two friendlies against Bordeaux and Nice, Keane was kept on his toes by the close attentions of defender Lequi but still pulled the strings in the first half.
Defoe then entered the fray at half-time and secured our third win in three friendlies at our training camp in France with a two-goal blast in as many minutes.
The first half was a tough test for the Irish star as Lequi barely left his side but typically of Keane, he dropped deep to pick up the ball and was involved in most of our positive attacking play.
That included two inch-perfect passes to release Wayne Routledge inside his full-back - the first ended in what must have been a close offside call as Routledge prepared for a shot on goal, the second ended with Rouledge flat on his face via Lequi but the referee waved away all appeals for a penalty.
At the other end, King and Davenport had to snuff out danger a couple of times and Hossam Ghaly coped well in an unaccustomed right-back role.
Martin Jol made five chances going into the second half and it was barely two minutes old when Defoe stated his intentions, racing onto Routledge's pass but unusually missing the target from 10 yards.
He made amends three minutes later with lightning reactions to open the scoring. Keane was involved again, this time his slide-rule pass released Ziegler into the left channel of the box and the youngster struck across Pinto only to see his effort cannon back off the inside of the post - Defoe was alert to it however and dived to head home from close range.
It was soon 2-0 and game over as Defoe struck again. This time Tainio picked out his run and Defoe coolly lifted the ball over the advancing Pinto before tucking it into an empty net.
Chances then came and went at both ends - De Ridder went closest for Celta Vigo when his volley zipped just wide while at the other end, Jamie O'Hara, Tainio and Berbatov might have added to the total, but it didn't matter, the job was done.
5mins: Vila's free-kick deflected and hacked away by Ghaly, who has started at right-back.
12mins: Nunez onto loose pass, managed to get in cross that King dived to head clear at near post.
15mins: Quick feet from Baiano took him away from Ghaly, unleashed drive from 25 yards that Davenport blocked superbly.
20mins: Pinto out of his box to head clear as Keane attempted to get onto Davids' pass.
27mins: Good spell of possession ended with Keane threading through what looked like a perfect pass to release Routledge on goal but the move was halted by the linesman's flag.
32mins: Potential danger as Baiano dinked pass into Guayre, almost got the better of Cerny but King there to mop up.
43mins: PENALTY? Looked a good shout as Keane threaded pass inside full-back again for Routledge, he cut inside Lequi and went down, appeals waved away.
Half-time: Celta Vigo 0, Spurs 0
Half-time: SUBS. Huddlestone, Dawson, Defoe, Berbatov and Tainio for King, Davenport, Davids, Murphy and Barnard. Celta Vigo swapped full team apart from goalkeeper.
47mins: CHANCE. Routledge chipped pass to Defoe, who beat offside trap and was through on Pinto but struck just wide from 10 yards.
50mins: GOAL. Keane threaded another pass inside full-back this time to Ziegler on left, he took shot first time that cannoned back off the inside of the post but Defoe dived in to head home rebound.
Celta Vigo 0, Spurs 1
52mins: GOAL. Defoe latched onto Tainio's pass over the top, lobbed the ball over the advancing Pinto and slotted into the empty net.
Celta Vigo 0, Spurs 2
62mins: De Ridder good technique to volley Vela's cross on full, ball arrowed across Cerny but a yard wide.
64mins: Great turn from Berbatov who then fed in Defoe down left channel, chipped to Keane at far post, he left Yago Yao for dead before laying back to Tainio who angled his shot just wide from 18 yards.
65mins: SUBS. Ifil and O'Hara for Routledge and Ziegler.
66mins: CHANCE. Vela volleyed back De Ridder's deep cross but Guerrero hit his snap shot wide from 12 yards.
70mins: SUB. McKenna for Keane.
71mins: CHANCE. Defoe cut in from left and rolled ball back for O'Hara who snatched his shot wide from 10 yards.
80mins: Berbatov good play to spread ball wide to Tainio and then dart in to box to meet the cross, couldn't get enough on effort at far post.
85mins: SUB. Lee for Ghaly.
Full-time: Celta Vigo 0, Spurs 2
Celta Vigo: 1st half: Pinto, Oubina, Lequi, Nunez, Angel, Baiano, Gustavo Lopez, Placente, Contreras, Guayre, Vila. 2nd half: Pinto, Richy, Roberto, Guerrero, Perea, Roberto, Vela, Yago Yao, Aspas, Jorge, De Ridder.
Spurs: Cerny, Ghaly (Lee, 85), Assou-Ekotto, Davids (Tainio, 46), Davenport (Dawson, 46), King (Huddlestone, 46), Routledge (Ifil, 65), Murphy (Defoe, 46), Barnard (Berbatov, 46), Keane (McKenna, 70), Ziegler (O'Hara, 65). Unused subs: Fulop, Barcham.
Robbie Keane completed 70 minutes on his return to action against Celta Vigo on Tuesday night - but Jermain Defoe stole the show in Annecy.