The Magpies spent big, by Championship standards, last summer on Dwight Gayle and Matt Ritchie. The duo helped Benítez's men return to the top-flight immediately after their disastrous relegation in 2016.
Newcastle have been far from inactive this summer, signing Jacob Murphy, Florian Lejeune, Christian Atsu and Javier Manquillo. But the club is expected to secure further signings before the window closes with tensions reportedly growing between Benitez and the club's board.
Here we analyse the top five Newcastle transfer rumours, using the Football Whispers Index, which rates each rumour’s probability out of five.
Calum Chambers – 3.7
Following the departures of Vurnon Anita and Kevin Mbabu, Benítez is searching for defensive reinforcements – and Calum Chambers is a name that has popped up regularly in recent weeks.
Chambers impressed on loan at Middlesbrough last season but is expected to leave Arsenal, with Laurent Koscielny, Per Mertesacker, Gabriel and Shkodran Mustafi all ahead of him in Arsène Wenger's pecking order.
The 22-year-old's ability to operate either in central defence or at right-back means he would be an extremely useful acquisition for Newcastle but, as with Lucas Pérez, they are said to have balked at Chambers' valuation.
Crystal Palace are also interested in Chambers so, if Newcastle want him, they may need to act swiftly and decisively with £16million believed to be the asking price.
Sam Clucas – 3.3
Newcastle have been heavily linked with a move for Hull City midfielder Clucas all summer. But they face competition from other Premier League clubs with Leicester City, West Bromwich Albion and Burnley also said to be interested.
Clucas enjoyed a stellar campaign for the Tigers last season as a string of solid performances at the heart of midfield helped him win the club's player of the season award, explaining why he has become a Newcastle target.
Leonid Slutsky's Championship side are willing to accept a bid of around £8million for the 26-year-old. But Newcastle are said to value him closer to £4million.
However, Clucas – who holds the unique honour of having scored in the top five tiers of English football – is keen to leave Hull with the option of an immediate return to the Premier League on the table.
In addition, Clucas was watched by Gareth Southgate's scouts last season so he may feel performing in the top-flight will give him the best opportunity of breaking into the England team.
Joselu – 3.0
Despite having Gayle, Aleksandar Mitrović and Ayoze Perez to share the responsibility of goal-getting this season, Benítez wants to bolster his striking force following the departure of Daryl Murphy – and has already seen an opening bid rejected for Stoke City's Joselu.
There is a strong possibility that Newcastle will secure the Stoke striker's services before their opening game of the season against Tottenham Hotspur. But they will need to improve their bid after the first was reportedly branded ‘derisory' by the Potters.
Although the Spaniard only managed four goals in 27 appearances for Stoke last season, he has impressed with four goals during pre-season and is a player Benítez has a long-standing interest in.
Some Newcastle supporters would prefer a move for Arsenal's Pérez but, with the Magpies reportedly not willing to pay £13million for his services, a move for Joselu seems more realistic at this stage.
Islam Slimani – 2.7
With the £25million arrival of Kelechi Iheanacho at Leicester City, Islam Slimani looks surplus to requirements at the King Power Stadium.
It's certainly been a disappointing chapter for the Algerian forward, who became the Foxes' record signing last summer when he signed from Sporting Lisbon for a £29million.
The 29-year-old reportedly wants to stay in the Premier League, perhaps feeling as though he has a point to prove. But Leicester will want to recoup most of the fee they spent on him which may scupper a potential switch to Newcastle.
Which is a shame, from a Newcastle perspective, as Slimani is arguably an upgrade on Joselu.
Although his debut season at Leicester was underwhelming, Slimani showed flashes – particularly in the Champions League – of his mobility, finishing ability and prowess as an out-and-out striker, something Benítez would welcome to his ranks with open arms.
Adama Traore – 2.0
A move for electrifying Middlesbrough winger Adama Traoré looks all but dead now that Newcastle have signed Murphy from Norwich City.
Perhaps that's just as well. Murphy scored nine goals in 40 appearances for the Canaries last season, while Traore, for all his raw talent and blistering pace, failed to score for Boro.
In Murphy, Newcastle have signed a more developed, rounded player who supported the Magpies as a boy. Signing Traoré, possibly for a similar fee, would have been significantly riskier.