ROBERT, La. - BP was confident Saturday its latest experiment using a mile-long pipe would capture much of the oil flowing into the Gulf of Mexico, even as the company disclosed yet another setback in the environmental disaster.

Engineers hit a snag when they tried to connect two pieces of equipment a mile below the water's surface. BP PLC chief operating officer Doug Suttles said one piece of equipment, called the framework, had to be brought to the water's surface so that adjustments could be made to where it fits with the long tube that connects to a tanker above.

The framework holds a pipe and stopper, and engineers piloting submarine robots will try to use it to plug the massive leak and send the crude through the lengthy pipe to the surface.

"The frame shifted, so they were unable to make that connection," said Suttles, who believes the adjustments will make the device work.

At least 210,000 gallons of oil have been gushing into the Gulf of Mexico since an oil rig exploded April 20 and sank two days later. Eleven people were killed in the blast.

BP's latest idea seems to have the best chance for success so far, said Ed Overton, a LSU professor of environmental studies. At the surface this would be easy, Overton said, but using robots in 5,000 feet of water with oil gushing out of the pipe makes things much more difficult.

"It's something like threading the eye of a needle. But that can be tough to do up here. And you can imagine how hard it would be to do it down there with a robot," Overton said.

The tube could capture more than three-quarters of the leak; BP also must contend with a smaller leak that's farther away. If the tube works, it would be the first time the company has been able to capture any of the oil before it fouls the Gulf waters.

A week ago, the company tried to put a massive box over the leak, but icelike crystals formed and BP scrapped that plan.

BP is also drilling a relief well that is considered the permanent solution to stopping the leak. It's about halfway done and still months away from being completed. The company also is still considering using a smaller containment dome known as a "top hat," as well as a "junk shot," in which golf balls and rubber would be inserted to try to clog the leak.

Meanwhile, BP began spraying undersea dispersants at that leak site and said the chemicals appear to have reduced the amount of surface oil.