Lotus will announce Kimi Raikkonen's replacement for the final two races of this season in "due course" with Davide Valsecchi leading the running.
On Sunday, it emerged that Raikkonen could sit out the United States and Brazilian GPs despite having reached a deal with Lotus regarding his unpaid salary.
However, it is not finances that are keeping Raikkonen out of the car, rather it is his back.
His manager Steve Robertson announced that the Ferrari-bound driver would undergo surgery on Thursday on an old back injury that was still causing him trouble.
As such, Raikkonen will miss the final two races of his Lotus career.
The team later confirmed the Finn's absence, however, did not at the time announce his replacement.
"Lotus F1 Team can confirm that Kimi Räikkönen will miss the final two races of the 2013 Formula One season to undergo, and recover from, back surgery," read a statement from Lotus.
"The team will make an announcement about the replacement driver for the United States and Brazilian Grands Prix in due course."
Lotus test driver Valsecchi is leading the running to replace the Finn, however, has only been in action twice this year, once during the pre-season and then again in the Young Driver Test.
But despite his lack of experience in the car, the Italian is down as Lotus' official reserve driver.
Back surgery sidelines Kimi