Real Madrid don't really have too many worries when it comes to the transfer market; more often than not they'll get who they want, whatever the cost, whatever the timing.
That's not the case for every player, though. AS Monaco forward Kylian Mbappe looks set to wear Paris Saint-Germain colours rather than those of Real Madrid next term, per Sky Sports, which perhaps leaves the Santiago Bernabeu hierarchy thinking they might want to do some extra business on the final day as a result.
Despite having the best XI, and the deepest squad, in Spain—maybe even in Europe, judging by back-to-back UEFA Champions League titles—there remain question marks over just one or two areas.
So, if their own targets are out of the question, which other clubs' moves should Real look to jump on to in last-minute deals?
We've spoken to journalists, fans and social media accounts to find out exactly what Los Blancos should be doing before the La Liga transfer window closes at 11:59 p.m. CEST on Friday.
Depth in defence: Part 1
A common theme when speaking to our Real Madrid influencers was that the back line needs another body.
Jesus Vallejo is back from loan spells and Theo Hernandez has been signed, but the central defence has already been whittled away and the names in place have history for missing games: Sergio Ramos through suspension, Raphael Varane through injury and Nacho because he can cover other positions.
After starting Sunday's game against Valencia with Nacho and midfielder Casemiro at centre-back, Real Madrid needing to reinforce this area is a popular opinion.
Television sports anchor Semra Hunter, formerly of Real Madrid TV, picks a big-name centre-back to fill the void.
"If you had asked me the same question a few weeks ago, I would have said Mbappe hands down. He's unquestionably gifted and scores tons," she told Bleacher Report.
"But, after seeing the last couple of games for Real Madrid, I would actually say I don't really think they need him (not right now, anyway) or anyone else up front considering what they have with Marco Asensio, which is special.
"In truth, I don't think they really need to bring someone else in right at this very moment, but it wouldn't hurt to add another defender. Of those on the market, I would maybe say Southampton's Virgil van Dijk.
"He's one of the Premier League's best defenders, he's got a very solid build, technically gifted, good in the air, he can create, he's the right age; an all-round complete defender."
The Saints man has not been involved with the senior side so far this season, and he remains the subject of bids from Liverpool and interest (at least) from Chelsea and Arsenal, per Miguel Delaney of The Independent.
It's expected the Dutchman will depart St Mary's Stadium before the English transfer window shuts at 11 p.m. BST on Thursday, though it will require a huge investment—£70 million or more—to ensure his signature.
He isn't the only option, though.
Journalist Sonja Nikcevic notes that the attack seems in need of reinforcement but centre-back might take precedence.
"The Valencia match showed that Real need another striker to score when Cristiano Ronaldo isn't available to make the difference," she said. "The problem, as usual with Real, is who to bench; although many fans are screaming for it to be Gareth Bale or Karim Benzema—or both.
"Other than that, a centre-back hijack is necessary for when Ramos is carded and Varane injured, which is not rare.
"Benedikt Howedes could be an option as someone who has the authority to be that backup option without necessarily demanding a first-team presence at all times. Aymeric Laporte is also a possibility although summer rumours had Sergio Ramos saying he didn't want him at Real Madrid from Athletic Bilbao."
Germany international Howedes is an aggressive, rugged and committed defender, but he is on the verge of a move from Schalke 04 to Juventus, per ESPN FC. An initial bid was rejected, but the 29-year-old—who can also cover at full-back, which might interest some fans—is capable of operating at the elite level.
As for Laporte, he is regularly linked with a move away, but Diario Gol (in Spanish) reported that while Zidane is a fan, Ramos is more inclined to side with Vallejo's improvement as the future of the team.
Depth in defence: Part 2
"Danilo's departure left a hole. Having watched Achraf Hakimi with Castilla regularly last season, I wouldn't have gambled on him just yet," Kiyan S. from the site said.
"Dani Carvajal's understudy is the most urgent role to fill, and while Hakimi is a really promising player with a ton of pace on the flank, I wanted to see him take a stepping stone first the way Marcos Llorente, Jesus Vallejo and others did.
"I've been a huge admirer of Alvaro Odriozola (21) and think he's Carvajal's successor in the national team.
"Already at a young age, he has La Liga experience and has started this season on a blitz. There's no real rush with shoehorning Achraf in right now, but I would've taken a bite at Odriozola."
Odriozola, who was linked with Barcelona towards the end of last season and the start of summer, per Marca, signed a new contract in June with a buyout clause of €50 million, per Cadena SER (link in Spanish).
Given the prices some full-backs have gone for this summer—not just Danilo but also Bernard Mendy, Kyle Walker and Nelson Semedo—perhaps Real Madrid won't baulk at paying somewhere in that region once Carvajal is ready to step aside.
There's an alternative, though: Sign someone capable of playing at right-back but who also offers an option elsewhere in the team.
"Hijack Fabinho to PSG," was its response.
"Alexis Sanchez to Manchester City has got me thinking...but a defensive midfield/right-back hybrid, and with Fabinho having already played at Castilla, would be cover for the one position we don't have an alternative to—Carvajal at right-back."
Fabinho may have to look elsewhere for a Monaco exit after reports that talks had broken down, per SFR Sport (h/t Get French Football News). If he's genuinely available for a move, though, there will be no shortage of takers.
The 23-year-old, who played once for Real Madrid's first team at the end of 2012/13, was a key part of the title-winning campaign Monaco enjoyed last term—but an exodus over summer means it will be partly a new team there for 2017/18.
Questions in attack
Although none of our quartet eventually went for a forward as their one go-to deal to hijack, more than one mentioned the attacking line as an area of concern.
With Alvaro Morata and Mariano gone, it's true there isn't the depth in attack of last year—Borja Mayoral is back for now, but he isn't of the quality or consistency needed to deliver off the bench or as an irregular starter.
Will the Mbappe deal be one that Madrid go on to regret? Should Zidane change his mind and go big on one more player in the forward line?
Deadline day gives Real Madrid one final chance to do so.
Quotes obtained firsthand unless stated.