The driver space wasn't maintained well in the small-overlap impact, with 11 inches of intrusion measured at the lower door hinge pillar.

Nissan's new Titan pickup has been excluded from the Insurance Institute for Highway Safety's Top Safety Pick ranks, earning a surprising 'marginal' rating in the small-overlap test.

The small-overlap test is considered the most challenging crash scenario in the IIHS assessment program. It was introduced five years ago, however, and nearly all US vehicles redesigned since 2012 now earn a 'good' rating.

For the latest Titan, the driver space was not well maintained. Intrusion reached 11 inches at the lower door hinge pillar, with dummy measurements indicating a risk of serious injuries to the left lower leg in a similar real-world crash of the same severity. Left foot and right lower leg injuries also would be possible, according to the report.

"The performance of the Titan crew cab contrasts with another large pickup that was redesigned for 2017, the Honda Ridgeline," the IIHS notes. "The Ridgeline, which was included in the initial list of TOP SAFETY PICK+ winners announced in December, is the only pickup so far to earn a 2017 award from IIHS and the third, after the Ford F-150 crew cab and extended cab, to achieve good ratings in all five of the Institute's crashworthiness tests."

Some automakers make quick changes to the vehicle structure to improve performance in the small-overlap crash. It is unclear if Nissan plans to follow the same strategy with the Titan.