Horner: We’re going to need eight or nine engines (lemon Renaults)

Sebastian Vettel smiles every time he's reminded he no longer has a lemon Renault engine

Red Bull's Christian Horner reckons both Daniel Ricciardo and Daniil Kvyat will need around nine engines if they're to go a season without facing a penalty.

Currently Ricciardo has used three engines and will use his fourth at the Spanish Grand Prix in just over two weeks time. Meanwhile Kvyat has enjoyed better reliability and is on his second.

Each driver is allowed just four complete power units per season – though this looks likely to increase to five – before they incur a 10-place grid penalty for each new unit.

Ricciardo has already admitted that penalties are now inevitable, saying: "We're going to get copped with at least one," but team boss Horner believes it'll be much worse.

"It is frustrating," he told the official Formula 1 website. "For sure we are going to use more than four – we've used three in three races – so the chances of us staying within the limit of four is close to zero.

"For us we would need that number to increase to seven, eight or nine engines for the season," he admitted.

The Briton is hopeful that the rules will change in the future to allow for such eventualities which are outside of Red Bull's control.

"Unfortunately these are the rules and we are not looking great within these rules," he added. "Hopefully these rules will become more realistic in the future."