Two preflop decisions with the same pocket pair against the same button open. Nothing changes between them except the size of the stacks — and that alone changes the answer.
Hand info
MTT, 9-max. Blinds 0.5 / 1, 12.5% ante — 1.125bb dead before anyone acts.
PREFLOP · 15BB EFFECTIVE · ANTE 0.125BB
BTN OPEN
9-max table. Hero is BB with 15 big blinds effective. BTN OPEN. Hero holds 9s and 9d. UTG is short-stacked at 15 big blinds. UTG+1 is short-stacked at 15 big blinds. UTG+2 is short-stacked at 15 big blinds. LJ is short-stacked at 15 big blinds. HJ is short-stacked at 15 big blinds. CO is short-stacked at 15 big blinds. BTN is short-stacked at 15 big blinds. SB is short-stacked at 15 big blinds. BB is short-stacked at 15 big blinds.
Hand history
Pre-flop
Mid-tournament, 15bb effective. It folds to the button, who min-raises to 2bb. The small blind folds. You are in the big blind with 9♠9♦ and 1bb more to call into a 4.625bb pot.