Cook pummelled 23 boundaries to all parts of George Park 1 during his 204-ball stay at the crease, carrying his bat the whole way through Cavaliers' innings.

Aside from a 99-run stand with Mitch Black (36), Cook was the anchor as wickets fell around him, with Hugh Middleton (11), Matt Corben (19), Cam Laird (8), Harry Pearce (4) and Gus Cumming (3) all part of the revolving door of partners at the other end.

Corben's 19 was the first time this season the competition's leading run-scorer has failed to bring up a personal milestone with the bat after a blistering start to the summer before Christmas.

The skipper waited for the 19-year-old to bring up his 150 in the 69^th over before declaring at 7-286.

He sent the hosts in to face nine overs and found reward as Corben and Black combined to have Mick Hutchinson stumped for six, leaving Bulls 1-18 at the close of play, 268 runs in arrears.

While Cook's no stranger to whacking massive tons, Saturday's mammoth score was a sharp turnaround from his pre-Christmas form, where his highest BOIDC score was just 21, with four single-digit scores at the top of the order.

He's had a bit more success in the shorter-format Royal Hotel Cup, where he's hit 24 and 30, but to say it was a relief to get the monkey off his back is an understatement.

"Oh for sure, absolutely," a relieved Cook said about getting the monkey off his back.

"I'd been hitting them pretty well in the nets but just not scoring early in the year ... it's definitely nice to hit some."

He said it was nowhere nearly the cleanest innings of his career, with the deck providing help to bowlers Cook admitted to plenty of plays and misses but the opener ground it out.

While he kept his pace "pretty consistent" throughout the innings, but knew a declaration was coming late in the innings as he and Mitch Maybin spied his teammates donning whites with the two lifting the scoring rate.