The phrase "a key performer" is correct and usable in written English.
It can be used to refer to someone who plays a crucial role in a particular context, such as a team, project, or organization.
Example: "In our recent project, Sarah was a key performer, driving the team towards success with her innovative ideas."
Alternatives: "a crucial contributor" or "a vital player".
Still just 25, he has time to come again as a key performer in white ball cricket for a county who need the big paydays more than most.
By cruel coincidence, two of London's biggest shows – in theatres within walking distance of each other on the South Bank – were lacking a key performer on Wednesday night.
With only two months in the majors, Chamberlain has become a key performer for a top team and a significant component of its personality.
Buffon, a key performer for Italy's World Cup-winning team two years ago, dived left and reached back with his hand to stop Mutu's shot, and the ball deflected away off his leg.
The fast bowler Harmison has been a key performer for Durham this season, while the opening batsman Trescothick has been instrumental in Somerset's pursuit of the County Championship title.
If Manning does become a turnover machine, it won't be because he makes poor choices while fleeing the Seahawks' rush; it will instead be because the football gods have decided to punish a quarterback whose college scouting report described him as "on his way to an outstanding N.F.L. career," in favor of a team with a key performer who's a "try-hard defensive tackle with stiff movement skills".
To be eligible for the award, a player must be in at least his second year of athletic eligibility, be a first-team or key performer and carry a cumulative 3.30 grade point average.
Forward Ryane Clowe, a key playoff performer, had his shoulder separated in the second round against Detroit.
Towards the end of the 1790s, Grimaldi starred in a pantomime version of Robinson Crusoe, which confirmed his credentials as a key pantomime performer.
One key performer will be Sergei Fedorov, 32, a center who was the league's most valuable player in 1993-94, whis his role expanded in the absence of Yzerman, who was injured.
Ernest Hemingway is the key performer in this charade, his characterisation of Stein as "a woman who isn't a woman" a crude mirroring of his own gender fears.
