The Irish centre will be determined to make his mark when Sir Clive Woodward's team face New Zealand Maori on Saturday.
"The games are getting fewer and fewer, the Test spots are up for grabs," said D'Arcy.
"I probably wanted to do everything against Argentina. I went in with too many goals.
"I wanted to make every pass, every tackle and it was never going to go like that. I felt more comfortable, more prepared going out in the Bay of Plenty game."
D'Arcy only got 10 minutes in Rotorua alongside Brian O'Driscoll, but it was enough to give him the necessary shot of confidence and he scored the Lions' final try after a gifted pass from Josh Lewsey.
O'Driscoll is looking forward to their partnership being renewed in earnest on the Test stage after it was interrupted so badly by D'Arcy's injury during the Six Nations.
"I don't think either of us is going to change our game in any shape or form," he said.
"We have played together I don't know how many times, at club and international level. I am thoroughly looking forward to playing with D'Arcy again.
"He is a world-class player and he has proven that over the last couple of years.
"The partnership in centre will be very exciting and hopefully we can play off each other and there will be an element of telepathy in what each other is doing."