Midfielder Piazon, 18, made his Premier League debut in the Blues 8-0 thrashing of Aston Villa back in December and will move to Spain for the remainder of the campaign.
“We have an agreement with Malaga, so Lucas will go there, and it’s a loan until the end of the season,” Benítez told a news conference on Tuesday.
Benítez also confirmed that Romelu Lukaku is unlikely to be recalled from his loan spell at West Bromwich Albion before the end of the season.
Lukaku has been in impressive form at The Hawthorns, scoring nine goals in 22 appearances in all competitions this season.
The Chelsea interim boss added: “Lukaku went there and is doing well, it’s part of his development, playing in the Premier League and getting experience.
“We will see, you never say never because something may happen tomorrow and you have a problem, but at the moment the idea is for him to stay there and gain more experience.”
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