Rio Hondo WTCC: Jose Maria Lopez and Yvan Muller head practice

Local hero Lopez was quickest of all in the first session, which got under way following a 45-minute delay due to the pilot of the medical helicopter arriving late after weather conditions hampered his journey to the circuit.

The current championship leader was quick from the off and demoted Muller from the top of the timesheets with his first flying lap with a time of 1m45.505s.

Lopez then made further improvements and managed to whittle it down to 1m43.889s, to become the only driver of the day to dip below the 1m43s barrier.

Team-mate Sebastien Loeb was his closest rival in the first session and ended up 0.260 seconds adrift, having constantly set the quickest time in the first sector but unable to hook up the perfect lap to go top.

The three Citroens were split by Mehdi Bennani, who found late gains in his Proteam Honda Civic to go third, ahead of reigning champion Muller, while Gabriele Tarquini was the fastest of the factory Hondas in fifth.

It looked like Lopez would also top the second session as he went quickest in the early running, but in the final 10 minutes of final practice, Muller managed to pull out a lap of 1m44.214s to put him ahead of his Citroen team-mate.

They maintained their positions until the end, while Tom Chilton found speed in the dying moments to put his ROAL Chevrolet third and just 0.071s off the ultimate pace.

Nine-time World Rally champion Loeb finished fourth. Tarquini was the fastest Honda in fifth, just ahead of team-mate Tiago Monteiro, and Hugo Valente and Nobert Michelisz occupied seventh and eighth in their Campos Chevrolets.

Tom Coronel had a disastrous second session as the Dutchman was forced to pit with smoke bellowing from the rear of his Chevrolet Cruze.

The ROAL mechanics soon extinguished the flames and they now face the challenge of preparing the car ahead of qualifying later on Saturday.

Practice one:

Pos  Driver              Team/Car           Time       Gap
 1.  Jose Maria Lopez    Citroen            1m43.889s
 2.  Sebastien Loeb      Citroen            1m44.149s  +0.260s
 3.  Mehdi Bennani       Proteam Honda      1m44.288s  +0.399s
 4.  Yvan Muller         Citroen            1m44.298s  +0.409s
 5.  Gabriele Tarquini   Honda              1m44.528s  +0.639s
 6.  Norbert Michelisz   Zengo Honda        1m44.675s  +0.786s
 7.  Tiago Monteiro      Honda              1m44.719s  +0.830s
 8.  Tom Chilton         ROAL Chevrolet     1m45.259s  +1.370s
 9.  Hugo Valente        Campos Chevrolet   1m45.302s  +1.413s
10.  Dusan Borkovic      Campos Chevrolet   1m45.541s  +1.652s
11.  Rob Huff            Lada               1m45.541s  +1.652s
12.  Gianni Morbidelli   Munnich Chevrolet  1m45.747s  +1.858s
13.  James Thompson      Lada               1m46.162s  +2.273s
14.  Tom Coronel         ROAL Chevrolet     1m46.197s  +2.308s
15.  Rene Munnich        Munnich Chevrolet  1m46.455s  +2.566s
16.  Mikhail Kozlovskiy  Lada               1m46.617s  +2.728s
17.  Franz Engstler      Engstler BMW       1m50.133s  +6.244s*
18.  John Filippi        Campos SEAT        1m51.655s  +7.766s*
19.  Camilo Echevarria   Engstler BMW                         *

* TC2

Practice two:

Pos  Driver              Team/Car           Time       Gap
 1.  Yvan Muller         Citroen            1m44.214s
 2.  Jose Maria Lopez    Citroen            1m44.254s  +0.040s
 3.  Tom Chilton         ROAL Chevrolet     1m44.285s  +0.071s
 4.  Sebastien Loeb      Citroen            1m44.364s  +0.150s
 5.  Gabriele Tarquini   Honda              1m44.472s  +0.258s
 6.  Tiago Monteiro      Honda              1m44.525s  +0.311s
 7.  Hugo Valente        Campos Chevrolet   1m44.647s  +0.433s
 8.  Norbert Michelisz   Zengo Honda        1m44.737s  +0.523s
 9.  Rob Huff            Lada               1m44.981s  +0.767s
10.  Rene Munnich        Munnich Chevrolet  1m45.119s  +0.905s
11.  Dusan Borkovic      Campos Chevrolet   1m45.245s  +1.031s
12.  Mikhail Kozlovskiy  Lada               1m45.435s  +1.221s
13.  Mehdi Bennani       Proteam Honda      1m45.788s  +1.574s
14.  Gianni Morbidelli   Munnich Chevrolet  1m46.146s  +1.932s
15.  James Thompson      Lada               1m46.201s  +1.987s
16.  Tom Coronel         ROAL Chevrolet     1m46.679s  +2.465s
17.  Franz Engstler      Engstler BMW       1m50.781s  +6.567s*
18.  John Filippi        Campos SEAT        1m51.293s  +7.079s*
19.  Camilo Echevarria   Engstler BMW                         *

* TC2