WASHINGTON — The Navy has relieved the two top officers of the destroyer John S. McCain, nearly two months after the ship collided with a tanker while approaching Singapore, leaving 10 sailors dead.

The commanding officer, Cmdr. Alfredo J. Sanchez, exercised “poor judgment,” and the executive officer, Cmdr. Jessie L. Sanchez, displayed “poor leadership of the ship’s training program,” according to a statement issued Wednesday by the Seventh Fleet in Yokosuka, Japan.

While an investigation is continuing into the Aug. 21 accident, the statement said that it was “evident the collision was preventable.” Both officers were relieved by Vice Adm. Phil Sawyer, the Seventh Fleet commander, “due to a loss of confidence.”

The dismissals are the latest fallout from the four Navy accidents this year in the western Pacific, including two fatal crashes: the John S. McCain’s collision and the destroyer Fitzgerald’s collision with a freighter in June near Tokyo.