The Illawarra Hawks have roared home in the fourth quarter to defeat Adelaide 36ers 98-89 in the NBL Cup.

Both teams entered Thursday's clash at Melbourne's State Basketball Centre in dire need of a win having lost five of their past seven outings.

But with the scores level after three quarters, it was the Hawks who broke through for a morale-boosting victory by outscoring the Sixers 26-17 in the final period.

Tyler Harvey paced Illawarra with 24 points while Deng Adel (19) and Cam Bairstow (14) combined for 19 points in the fourth quarter to see the Hawks improve their season record to 7-5.

Illawarra coach Brian Goorjian praised his squad for rising to the occasion after some patchy performances in recent weeks.

"We've lost some close ones then we got pounded a little bit and we've been struggling, so tonight was desperation," he said.

"We were desperate and I coached desperate - I was tighter with my rotations and we made a few adjustments."

Coming off a 44-point drubbing at the hands of the New Zealand Breakers, Adelaide showed greater urgency and control from the outset on Thursday, with Sunday Dech (14) knocking in two of their four three-point makes in a 27-21 start.

Three first-quarter fouls to centre AJ Ogilvy seemed to unsettle the Hawks but they did a better job of getting shooters Harvey and Justinian Jessup open in the second quarter, a 17-10 run seeing them hit the lead for the first time.

But Tony Crocker finished with 13 first-half points and the Sixers committed just one turnover to take a 48-46 edge into the main break.

Harvey continued to heat up for the Hawks, opening the second half with his fifth three-pointer, but Josh Giddey stepped up with 10 points for the term and Jack McVeigh drilled a late basket to tie the scores at 72-72 with one quarter to play.

Illawarra opened the final term on a 9-0 run and the Hawks drove home their advantage, Adel deadly from long distance to break Adelaide's resistance.

Crocker finished with 23 points in a losing effort while Daniel Johnson (17), McVeigh (16) and Giddey (14 points, nine assists, six rebounds, three steals) kept Adelaide in the hunt during a tight second half.

Sixers coach Connor Henry felt his side bounced back well from their recent poor showings while adjusting to the absence of centre Isaac Humphries for six weeks due to a foot injury.

"There was a good effort on the defensive end and there was probably 10 possessions or so on the offensive end where we didn't quite get the job done and that was the game," Henry said.