A device relieves the weight on the thumbrest of a woodwind instrument that does not have a curved neck near the mouthpiece, thereby avoiding muscular strain and soreness in the right hand and thumb of the instrument player without altering negatively the instrument playing in the conventional ways. This device includes a strap 20 that suspends on the player's chest an enclosure 30 housing a constant-force spring 34 coupled with a coil of cord 40 which terminates outside of this enclosure in a snap-hook 60 that is secured onto the thumbrest ring 70 of the instrument. In usual playing positions that point the instrument to the ground, the device creates a physical force component on the thumbrest in line with but opposite to the weight of the instrument on the thumbrest and thus diminishes in a perceivable manner the stress of the instrument weight on the right-hand of the player.