be slipping

be slipping

To be deteriorating in quality or performance. This dish tastes strange—I think the chef is slipping.
See also: slip

be ˈslipping

(informal) (of somebody’s behaviour or performance) not be as good, tidy, efficient, etc. as usual; not be up to somebody’s usual high standard: You’re slipping, Edwina: this letter is full of typing errors.That’s three times he’s beaten me — I must be slipping!
See also: slip
References in classic literature ?
"I think he must be slipping," at last I heard him sigh.
When they return, Mata hopes Man United will be ready to push for that Champions League place which currently seems to be slipping through their fingers.
To a world in which peace seems to be slipping, to a nation in which unemployment is on the rise, to congregations who know in their hearts that, if they keep on being who they are, they will someday cease to be, to pastors who are just plain tired, to people sick and shunned, oppressed and afraid, Christ comes!
He wanted to gulp in a few last breaths of tranquillity before the tension of a season that seems to be slipping away from him began to tighten its grip again.