F1: More drivers expected to sub in Caterham during 2014

Rookie Andre Lotterer is making his Formula One debut for Caterham CT05 Renault in this weekend's 2014 Belgian GP.

Spanish Renault 3.5 stars Carlos Sainz Jr. and Roberto Merhi are both in line to make their F1 debuts with Caterham before the end of the season.

It’s believed that they are in the frame to take turns driving the car occupied by Andre Lotterer this weekend.

As noted in the past, Sainz came into the frame around the time of the British GP when Red Bull discussed putting him in the Caterham for the rest of the season. Caterham uses a Red Bull gearbox, while team advisor Colin Kolles did a similar deal to put Daniel Ricciardo in an HRT in 2011. However, it was decided to allow him to concentrate on Renault 3.5.

Merhi, who won the 2011 Euro F3 title before spending two years in the DTM with Mercedes, has been in the Caterham at Spa motorhome this weekend.

Sainz and Merhi currently lie first and second in the Renault 3.5 series. The championship has three more weekends to run, none of which clash with Grands Prix.