With the 2018 Copa Libertadores champions under pressure to raise funds via player sales this summer, the Albiceleste starlet looks set for a move to Europe with Roma, Bayer Leverkusen, Real Betis and more all linked.
"He is an incredible player, I keep saying it and I mean it: he is huge for this club".
Speaking at the press conference, he said (as quoted by Football London): "Well, I hope the team can take comfort from it, we're looking for positives, we're looking for things to keep us nice and high".
"I think he has done well but the midfield have to improve as a unit with everybody together, the more we work on it".
Now let's be honest.
Moyes, 57, returned for a second spell as manager of the club in December, replacing Manuel Pellegrini and signing an 18-month deal. And Moyes is clearly flustered.
And West Ham are suffering because of Moyes's ancient approach to tactics and in-game management.
In fact, Marca claims that there is a "very firm possibility" that Montiel will be heading to the London Stadium, possibly as a replacement for retiring compatriot Pablo Zabaleta.
West Ham, who are 17th in the Premier League and above the relegation zone on goal difference, have finished in the top six three times since 1965.
In a way, it highlights just how inept Moyes is as a manager.
Because, as Montiel's agent himself has admitted to TNT, West Ham are still very much in the race to sign an global right-back despite having a £9 million bid laughed out of the door by River Plate five months ago.
Since the Premier League season restarted on 17 June, West Ham have lost to Wolves and Tottenham and are yet to score.
The only luck the Hammers need is for the owners to see sense and sack the Scot before it's too late.