NEW ORLEANS (AP) -- A Transocean (RIG -0.69%) employee who survived the Deepwater Horizon rig explosion says a subordinate killed in the blast was one of the workers who apparently missed signs that BP's (BP 0.71%) Macondo well was on the verge of blowing out.

Senior toolpusher Randy Ezell testified Tuesday at a trial designed to assign blame over the 2010 disaster in the Gulf of Mexico. Ezell said Jason Anderson was a "top-notch" toolpusher who would have done everything in his power to prevent the blowout. But Ezell says Anderson and others on the rig apparently misinterpreted the results of a crucial safety test.

Anderson was one of 11 workers who died on the rig. Ezell said Anderson told him less than an hour before the explosion that there were no signs of trouble.