The present invention relates to an apparatus for and a method of holding high top tension pipeline (101) during pipe-lay from a rolling and pitching vessel (730). In one implementation, a clamp system (711, 712) for supporting a pipe on a vessel includes a first clamp for coupling to the pipe and a second clamp for coupling to the pipe. The second clamp is disposed above the first clamp. At least one of the first clamp or the second clamp is movable relative to the other of the first clamp or the second clamp.