Although the loanee duo have struggled so far this season, there was a feeling that they were just regaining full match sharpness, so their absence will be a blow, especially to a side who have stuttered up front this season.
Without Sanches and Bony, Clement's options in attack look worryingly threadbare, and like any side who look destined to spend their campaign embroiled in a scrap to avoid the drop, he is likely to request signings in the January transfer window.
Here are five attacking players Swansea should target.
The Argentine striker may have signed a new two-year deal with Leicester City in August, but he has still found starts hard to come by under Craig Shakespeare, with Jamie Vardy, Shinji Okazaki and Islam Slimani all ahead of him in the pecking order.
The 31-year-old would offer the same aerial threat as Fernando Llorente, which became such an effective weapon in attack for the Swans last season.
Packing their frontline with the same presence could pay dividends, offering a different dimension to Bony. Pertinently for Swansea, too, Ulloa played a pivotal role in Leicester's march to survival at the end of the 2014/15 season under Nigel Pearson, including a goal against Swansea to move the Foxes off the bottom of the table.
It's exactly that clinical finishing and big-game mentality that could prove a real asset for Clement in the second-half of the campaign.
Despite snapping up Sanches from Bayern Munich in what was hailed as a coup, Swansea are still crying out for an attacking midfielder.
Although the club is expecting the Portugal international to improve, while there is a sense that we could still see the best of Roque Mesa, the void left by Gylfi Sigurdsson's departure has not been sufficiently filled.
Tom Cairney, the gem in Fulham's midfield, could certainly change that.
Cairney has not played since the win over Ipswich Town on August 26, and it's shown as the Cottagers have had a mixed bag of three wins, four draws and a defeat in his absence.
Last season, Cairney was outstanding. He was Fulham's top-scorer with 13 goals, but he also completed the most accurate passes in the Championship with 3352, most key passes with 118 and was the only player to reach double figures in both goals and assists as he lifted Fulham to the play-offs.
The Newcastle United target has been watched by Swansea scouts in the past, and January may be the time to pounce.
West Bromwich Albion winger Chadli wanted a move to Swansea in the summer, but the deal did not materialise when the Baggies refused to budge on their asking price.
The 28-year-old Belgian, signed from Tottenham Hotspur in 2016 for a club-record £13million, has fallen out of favour at the Hawthorns following an argument with Tony Pulis.
Swansea have been admirers of the player since he was at FC Twente but came closest to finally landing him in August, and they could revive their interest in January.
Chadli was an unused substitute for West Brom's first three league games and has been struggling with injury since. However, Chadli demonstrated his attacking talent last season, scoring five goals and adding five assists, while making 33 key passes in 31 appearances.
The Belgium international is capable of hot streaks, too, scoring four goals and adding two assists in his first five Albion games and such flashes of inspiration could be an outlet on the wing for Swansea. There remains question marks over his consistency and work-rate, but he could be a risk worth taking at this point.
Swansea were strongly linked with a move for Gayle in January 2016, offering Crystal Palace £7.5million for the striker.
However, Gayle stayed at Selhurst Park until the end of the season, helping to secure the Eagles' Premier League survival before moving to Newcastle.
Last season, Gayle was devastating for the Magpies as his 23 Championship goals lifted Rafael Benítez's side to automatic promotion.
However, following the signing of Joselu, Gayle has found himself starting most games on the bench and could be tempted by an offer of more regular first-team football.
Gayle has always been able to find goals even when he hasn't started regularly. In and out of the Palace line-up, he still finished as the club's top-scorer in all competitions in the three seasons he was there.
However, Benítez is willing to offload the 26-year-old having grown concerned over his attitude, but new surroundings at the Liberty Stadium could be just the antidote to his current woes on Tyneside.
More of a stretch than the previous four, yes, but there is no problem in showing ambition in the transfer market. Swansea certainly did that by securing Bony and Sanches and Clement could do a lot worse than to pursue the signing of this talented Dutch winger.
The Liverpool transfer target is an electric presence on the wing for Spartak Moscow, scoring six goals and adding three assists in ten Russian Premier League appearances this term.
— Bookmaker Ratings (@bookieratings) September 16, 2016
Although Tammy Abraham has been a welcome injection of pace and penetration, the 20-year-old cannot be expected to pull defences apart single-handedly. With Promes's trickery, crossing and eye for goal, he could add a riveting new dimension to the attack.
Recent reports have suggested that Jürgen Klopp will revive his interest in the 25-year-old in January, so the competition for his signature may be stiff. However, Swansea would represent a better opportunity for regular starting football, so it would certainly be worth enquiring.