Second pair with no spade functions as a bluff catcher; raising only bloats the pot and isolates us against hands that crush us.
Flop Analysis
Calling is the only play here. Raising with middle pair and no spade accomplishes very little—it folds out worse holdings we currently beat while bloating the pot against flushes, top pairs, and strong draws.
**Ranges:** Raising isolates us against the top of SB's continuing range like top pair or made flushes, while folding out hands like bare ace-high floats that we beat. Second pair functions purely as a bluff catcher and needs to keep SB's range wide.
**Math:** Facing a 2.3BB bet into a 6.5BB pot, we receive 3.8:1 pot odds and need under 21% equity to continue, making a flat call clearly profitable.
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> **Takeaway:** With marginal made hands on monotone textures, flat to keep bluffs in rather than bloating the pot without redraws.
Note: Raising middle pair with no spade overplays a marginal hand and isolates us against better holdings; calling keeps SB's bluffs in the pot.
Turn Analysis
Calling is the correct decision facing this bet. Shoving all-in accomplishes nothing positive because SB folds their bluffs and only calls with hands that have us crushed.
**Ranges:** SB's betting range includes low flush draws such as an offsuit ten with a spade alongside trips, overpairs, and completed flushes. Shoving folds out their missed draws while ensuring we only put our remaining stack in against hands that beat our two pair.
**Math:** Getting 4.1:1 on a call, we need only 19.5% equity to continue. Jamming turns a profitable bluff catcher into an overcommitted bluff.
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> **Takeaway:** When holding a pure bluff catcher, call to let missed draws keep barreling rather than shoving into monsters.
Note: Shoving all-in folds out SB's bluffs and isolates our hand against trips and flushes; flatting preserves EV.