The Black Eyed Peas star is seen in tears as the coaches pick their final acts for their teams in the last blind audition show of the series.
Going into the last day of filming, Kylie Minogue leads the way with eleven of her twelve acts chosen.
Ricky Wilson, Sir Tom Jones and Will meanwhile all have two free spots each leaving with seven more acts to find overall.
But finishing their teams won't be easy as the panel will have to decide whether or not to turn for acts and forgo the opportunity to press their buzzers any more, or risk saying no in the hope that another artist will come onto the stage and blow them away.
"Shall I press or shall I wait?" veteran coach Sir Tom asks himself in the last episode.
"You've just got to go in for the killer blow," Ricky adds.
Kylie says: "It's getting really tough."
However sneaky Willy is up to his old tactics and it doesn't go unnoticed by his fellow judges.
"Will's playing a dangerous game," Ricky warns.
But Will defends his actions, saying of one act he turned around for: "We're not messing around here. He could be the one that got away."
However by completing his team it means Will can't press his buzzer for any more acts, which leaves him in tears after listening to another audition.
Will sobs: "I'm sorry... thank you for singing today."
The Voice 2014 airs Saturday night on BBC One.