Bruno Senna made his one-stop strategy work, overtaking Nico Rosberg to finish in tenth position and claim one world championship point.
Pastor looked set to finish in the points, but his race was hindered by a right-rear puncture after contact with Kobayashi, and eventually finished in 16th.
The Williams-Renault FW34 has shown a clear improvement in pace this weekend and the team will be looking to build on this result in Abu Dhabi next weekend.
Mark Gillan, Chief Operations Engineer: We are pleased to see that the race pace is strong once more with Bruno coming home in tenth even though our race was ultimately compromised with traffic and Pastor's race effectively finished when he picked up a rear puncture when Kobayashi made contact with him in Turn 5 on lap 31.
It was a fun race because I was fighting with cars that were very similar on pace so I had to make my overtaking manoeuvres stick, and so that was very satisfying.
The car has felt much better this weekend so we will head to the next race with a lot more confidence.
Pastor Maldonado: The car was feeling good today and I was confident that I was going to score points, but my race was effectively over when I was hit and picked up a puncture which put me towards the back and lost me a lot of time.
It was a very unlucky race for me in the end, but we can take some positives in the fact that the pace of the car has improved and we should be more competitive for the final three races of the season.
Laurent Debout, Renault Sport F1 team support leader: Tenth position for Bruno is at least one point, but everyone expected more from the race.
It was a shame that Pastor lost some time with the puncture as the car has been quick this weekend. We’ll hope to get two cars in the points in Abu Dhabi.
Source: Williams F1 Team