This was a tiring afternoon for Bournemouth, who had 18 goal attempts but only hit the target with four.
Iraola's side were relentless in their pursuit of a goal and ramped up the pressure as the game went on, throwing numbers forward in an attempt to overwhelm the visitors. They registered 1.19 expected goals (xG) but could not put the ball away.
Full-back Milos Kerkez was instrumental in their attacking efforts and consistently looked to make positive moves, charging up the left flank with the ball at his feet to spark dangerous transitions.
They were far from one-dimensional on the front foot, though, with Justin Kluivert linking up play, Dango Ouattara causing trouble with his neat footwork and Semenyo regularly looking to take on Palace goalkeeper Dean Henderson.
Semenyo toiled in the final third throughout, slicing wide from the edge of the box and sending a powerful header to the side of Henderson's goal as he missed two excellent late opportunities.
Introducing Evanilson and Tyler Adams in the second half resulted in the momentum staying firmly in the Cherries' favour.
Brazilian Evanilson proved much tougher for the Palace defence to handle than the man he replaced, Enes Unal, but Bournemouth's efforts were fruitless despite them controlling the closing stages.
They sit sixth for now in the table, a point ahead of out-of-sorts champions Manchester City, with Palace remaining uncomfortably close to the relegation zone.