German Sutil will drive for Sauber in 2014, a team that like Lotus publicly struggled with its finances throughout last season.
But the 30-year-old driver indicated Sauber will definitely be at Jerez, where teams will have their first chance to put their 2014 cars through their paces, featuring all-new turbo V6 engines and energy recovery systems.
"This is a very important test," Sutil told Reuters, "and we don't have much (testing) so I think it's clear that it will be a disadvantage for Lotus.
"But who knows why they decided it? I would say it is definitely not good."
Sutil acknowledged, however, that difficult financial circumstances could also continue to hinder Sauber's progress, although he sounded confident the Swiss team will succeed.
"I think it's all in there, they have the knowledge of how to do it," he said.
"If that financial part comes better and better I think this team will make a big step."