Standard Liege winger Moussa Djenepo has passed his medical ahead of his imminent £14m move to Southampton.
A deal between the two sides was agreed on Wednesday, with the 20-year-old set to become the Saints' first addition of the summer if he is given a work permit.
Claes states that Southampton will pay an initial fee or around £10.6m, alongside some add-ons, with reports in England suggesting the entire deal will reach a total of around £14m.
The Mali international had been tracked by AC Milan, but it appears as though the Saints have won the race for his signature after, according to the Daily Echo, Hasenhuttl returned from his summer break early to focus on recruitment.
The hope is to sell a few players, whilst also bring in several new faces to ensure Southampton are not involved in a relegation battle next season.
Alongside Djenepo, the club have been linked with Everton's Ademola Lookman and Birmingham City's Che Adams, whilst Liverpool's Adam Lallana has also been tipped to make his return to St Mary's Stadium, although he recently insisted he would remain with the Champions League winners.
The focus is clearly on attacking players, as Hasenhuttl looks to create a dynamic forward line. Last season, no player managed more than seven Premier League goals, with James Ward-Prowse and Danny Ings leading the team's scoring charts as they narrowly avoided relegation.
The highly rated Djenepo also managed seven league goals last season, playing both as a winger and a central striker as Standard managed to qualify for next season's Europa League.
He offers the kind of versatility and dynamism that Hasenhuttl is looking for, and it remains to be seen whether he will be the only forward to arrive at the club this summer.