Nico Rosberg top in final Spanish GP practice

Rosberg experienced sensor problems in final practice

Nico Rosberg headed Mercedes team-mate Lewis Hamilton in final Spanish Grand Prix practice with Ferrari's Sebastian Vettel close behind.

Rosberg was 0.126 seconds ahead of Hamilton and Vettel just 0.021secs further adrift as the teams look set for a close battle for pole position later on Saturday.

Max Verstappen was fourth in another starring performance on his debut for Red Bull, heading team-mate Daniel Ricciardo.

Ferrari's Kimi Raikkonen was sixth after being held up on his fastest lap.

Hamilton had been unhappy with his car in Friday practice but was much closer on pace on Saturday morning.

Qualifying is live on the BBC Sport website and radio 5 live Sports Extra

However, Rosberg still appears to have an advantage over his team-mate, who needs to beat the German this weekend to start reducing his 43-point deficit in the championship.

Hamilton managed two flying laps on the 'soft' tyre - and while on the second lap he reduced the gap from 0.4secs, Rosberg did not get a second run because his engine went into a 'limp-home' mode.

Hamilton was fastest of all in the first two sectors of the lap but gave away 0.2secs to Rosberg in the final sector, which is all slow corners.

Ferrari look closer than they have done for some time, after a series of difficult races, but Mercedes always seem to pull out a good extra half-second when it comes to qualifying.

Mercedes, Ferrari and Red Bull look, on the face of it, set to be clearly the three quickest teams but there is a very close fight behind.

Williams' Valtteri Bottas headed that battle in seventh place but only 0.2secs separated him from Fernando Alonso's McLaren in 10th, with Force India's Sergio Perez and Toro Rosso's Daniil Kvyat in between.

Alonso's team-mate Jenson Button has been struggling so far this weekend and was 0.5secs slower than the Spaniard with 15th fastest time.

Alonso will be cheered on by thousands of adoring Spanish fans, many of them travelling from his home town of Oviedo in the north-west of the country.

Qualifying, which starts at 13:00 BST, is set to take place under blue skies on a so-far perfect Mediterranean spring day.

Spanish Grand Prix final practice results

Spanish Grand Prix coverage details

Max Verstappen was fourth fastest, in his first drive for Red Bull since his controversial move

Mechanics had to look at Lewis Hamilton's car yet again during final practice as he wasn't happy with the balance of it