A system and method for sealing a percutaneous puncture extending into internally located tissue, e.g., the peritoneum, of a living being. The system includes a reinforcing device and a deployment instrument. The device comprises a substantially rigid anchor, a resorbable holding member, a collagen plug, and a resorbable thin filament connecting the anchor, holding member, and plug in a pulley-like arrangement. The anchor or the plug or both may be formed of a resorbable material having a non-resorbable mesh reinforcement embedded therein. The deployment instrument includes a tubular carrier in which the closure and a tamping member are located. The tamping member is operated to expel the closure so that the anchor is in the interior of the peritoneum and the plug and the holding member are in the puncture tract, with both ends of the filament extending out of the puncture and with the holding member fixedly secured to a portion of the filament adjacent one end. The other end of the filament is then drawn proximally while the tamping is pushed distally to draw the anchor member against the tissue contiguous with the opening. The tamper mechanically deforms the plug within the tract. The extending ends of the filament are formed into a knot, a portion of which extends through the skin contiguous with the puncture, to lock the closure in place. The reinforced mesh of the closure reinforces any scar tissue which forms at the opening.