The defendant William Dolan moved for a physical examination under Mass. R. Civ. P. 35, 365 Mass. 793 (1974), of the plaintiff without the presence of counsel. The motion was allowed. The plaintiff then filed a petition for relief as a class action under G. L. c. 211, § 3, to establish his right to have counsel present at the examination. The single justice in the exercise of his discretion dismissed the petition. No abuse of discretion is shown here. We have previously stated that we are extremely reluctant to invoke G. L. c. 211, § 3, in matters of this nature which do not involve both the protection of a substantive right and the absence of an alternative, effective remedy. Costarelli v. Municipal Court of the City of Boston, 367 Mass. 35, 41-42 (1975). Whitmarsh v. Commonwealth, 366 Mass. 212, 215-216 (1974). Enbinder v. Commonwealth, 361 Mass. 871 (1972).

Judgment affirmed.