Mubakker let his supporters down when last seen but should be given chance to redeem himself in the Heed Your Hunch At Betway Handicap at Newcastle.
Michael Stoute's runner was sent off a 3-1 joint-favourite at Ascot back in October, but racing on soft ground in a competitive three-year-old only heat he was all at sea and finished seventh.
His pedigree suggests a sound surface would be much more up his street and he had previously shone on an artificial track when hammering his Kempton rivals by eight lengths.
Saddled with a 7lb penalty on that occasion, Mubakker quickened up in fine style and seemed to have a fair bit still in reserve crossing the line.
As a juvenile he also showed smart form, winning on his second start, and he merits respect as he returns to the fray.
Paul Hanagan has made no secret of the regard in which he holds Custodian and while injury prevents the rider from taking the saddle in the Betway Casino Handicap, the hint should not be ignored.
Hanagan is still sidelined following a terrible fall back in March, but he has given this Cheveley Park-owned colt some very favourable mentions in the last few weeks.
A son of Muhaarar out of a five-furlong Listed winner, Custodian's pedigree is all speed and while his inexperience appeared to cost him on his debut in terms of a tardy start, he made no mistake at the second time of asking.
Racing over six furlongs at Pontefract last August, Custodian hit the front a furlong from home and ran out a tidy three-length winner.
A starting mark of 83 might well prove lenient for Richard Fahey's charge given the buzz about the colt.
Raydiance can strike in the Betway Handicap after winning one of his three starts earlier in 2020, while Lockdown is sure to be a popular topical choice in the first division of the Betway/British Stallion Studs EBF Maiden Stakes.
Hailing from a winning family, he should be sharp enough to do himself justice for Hugo Palmer.
Kempton stages its first meeting following racing's return and Charming Kid can take a starring role in the Unibet Handicap.
Group Two-placed when trained by Fahey, Charming Kid transferred to Dean Ivory's care at the end of last year but hardly set the world alight.
However, he showed signs of a revival at Newcastle in February when finishing third in a competitive heat after racing a bit keenly in the early stages.
Dropped 1lb after that run to a perch of 82, that mark looks pretty generous considering he was rated 105 in his pomp.
Charming Kid is owned by the Cool Silk Partnership, as is Olympic Conqueror who runs in the Unibet Money Back Free Bet If Second Handicap.
Well-backed at Kempton over 12 furlongs in February, Olympic Conqueror justified that support when hanging on by a nose in a thrilling finish.
A winner over 10 furlongs last year, dropping back in trip might be just the ticket.
Also at Kempton, it might pay to take note of Frankie Dettori's sole ride of the day - and first of the week. That comes courtesy of Galsworthy in the Unibet Casino Deposit £10 Get £40 Bonus Maiden Stakes.
KEMPTON: 1.00 Hold Fast, 1.35 Olympic Conqueror, 2.10 Charming Kid, 2.45 Kawaalees, 3.20 City Walk, 3.55 Imrahor, 4.30 Galsworthy, 5.05 Really Super, 5.40 My Sister Jo.
NEWCASTLE: 12.45 Amplification, 1.20 Raydiance, 1.55 CUSTODIAN (NAP), 2.30 Mubakker, 3.05 Lockdown, 3.40 Victory Heights, 4.15 Imperial Butterfly, 4.50 Pelekai, 5.25 Mountain Ruler, 6.00 Sucellus.
DOUBLE: Custodian and Mubakker.