The Hawks were confident of retaining the Olympic Bronze Medallist had he chosen to return to Australia post-NBA Summer League, but it's understood the 26-year-old is set to take up a lucrative deal in China.

It's a bitter blow for the Hawks faithful after reigning Defensive Player of the Year Antonius Cleveland was also lured away by Adelaide on a big-money contract alongside management stablemate Robert Franks.

Illawarra also flirted with a bid for Thon Maker, but he's also tipped to ink a big deal in China, with NBL clubs no match for the huge dollars on offer in Asia.

Hawks president of basketball operations Mat Campbell said the club was confident Wollongong remained Reath's NBL destination of choice, but couldn't compete for his services financially against the might of cashed up Chinese club owners.

"We've had confirmation from his agent that Australia's not an option from his point of view," Campbell said.

"We were hopeful he wanted to do one more year in Australia and all indications were that, if he was going to play in Australia, he was going to play for us. His agent was good about that and Duop himself was really good about that.

"We were hopeful that the NBA was still a pathway for him and we still believe our league is the best pathway into the NBA across all of the leagues at the moment. Ultimately it comes down to what he feels is the best playing option for him and obviously, financially, [Chinese clubs] are on a different level to what we are from an NBL perspective.

"It is what it is, we're really happy with the way he played for us as a Hawk and wish him all the best."

Much of the Hawks recruitment strategy hinged on whether Reath would return to the NBL, with the club now forced to look at contingencies it had in place could it not secure the star big man's return.

Having confirmed the signing of former Charlotte Hornet Mangok Mathiang on Friday, Campbell said the import search will centre on a versatile forward to predominantly play in the four spot.

"[Reath departing] has left us in a bit of a hole from a recruitment point of view, and at a late stage, but we're not scrambling" Campbell said.

"We obviously had plans in place if he did [leave]. Obviously some of the players that were available three or four weeks ago aren't available anymore, but the good thing for us is that the fringe NBA guys are really interested in coming to Australia if they don't get their opportunity on a two-way contract or a roster spot.

"We're looking at a forward, a four-man in our league. The added bonus with now having Mangok in the team is that, with Sam [Froling], we're able to be more versatile in that. We might get someone who could swing to the three as a wing player whereas, if we were't able to shore up our bigs, we'd have probably needed someone who swings a little bit to the five.

"The versatility of that spot helps us in recruitment. We're obviously looking to replace Duop's attributes so we need someone who can shoot the ball and we're just looking for the best fit for our team. We've still got three roster spots left so those last two import spots are really key.

"It's important we get that right so we're not going to rush on that. We've got some good interest at the point-guard position which is really high quality. The four-man is a harder spot to find, but we've got some options there and, with a [import] point-guard in play, we'll be competitive."

Read more: Illawarra sign former NBA big-man Mangok Mathiang

The loss of Reath makes the signing of Mathiang a major coup, with the 29-year-old to bring huge inside presence alongside Froling and a likely import.

"We've followed Mangok for quite some time," Campbell said.

"He's been a really high-level European player, had a really good [US] college career and played a couple of games in the NBA. We've liked his toughness and other attributes.

"He's been under a bit of an injury cloud but there was an opportunity there for us given he really wants to get his stock back up and get back overseas.

"He's a complimentary piece to Sam Froling, I think he'll add a bit of value in that space from the centre position and a bit of toughness. It's something Sam can really learn off and its part of his evolution for him to develop as well.

"He's doing a good job with the Aussie team and over the past few years and I think Mathiang's international experience will really help develop Sam into a really high quality player as well."

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