Hello and welcome to our coverage of the second of the day's practice sessions ahead of Sunday's Korean Grand Prix.

And that concludes the session. Lewis Hamilton fastest with Jenson Button completing a one-two for McLaren.

Button very slow on his first lap on the dry rubber... and he tells the team he cannot get any heat into them.

Hamilton has soft rubber on his car for one last run.

Button wants supersoft tyres but Hamilton tells McLaren it is too wet for dry tyres.

Alguersuari out on supersoft tyres - perhaps he just wanted one run on these and there isn't a problem.

Senna spins again in his Renault - on intermediate tyres.

Alguersuari came back out but only lasted one lap. Looks like he has another issue.

There is sttill some water on parts of the circuit, especially the final corner - therefore many teams still using inters and not risking their chassis with a run on slicks.

He still leads the way, however, from Button and Vettel. The latter is back in the pits.

Hamilton off into the turn four grass and back on track.

Toro Rosso mechanics are working to mend Alguersuari's car in a bid to get it ready for another run.

The pieces of Rosberg's car have now been removed and the rest of the field can crank it back up.

Rosberg locks in turn one and slides into Alguersuari's Toro Rosso! It's a nasty bump and there's debris on the track.

Vettel's Red Bull isn't really threatening the McLarens at the moment. But a drying racing line might change that.

Half an hour remaining...

Alonso now climbs into third place after a 1m52.774s...

Alguersuari, who paced the opening stages of the session, is in sixth.

Alonso nearly joins the big boys with a lap of 1m53.158s - the Ferrari man settles for fifth.

Hamilton returns to the track and nearly tops his own benchmark time of 1m50.828s with a quick final sector.

Ferrari on their Twitter feed: "Fernando is coming in: once more, nose change and then out again."