The St. Louis Blues are used to injuries altering their lineup. It’s happened a lot this season. But playing the Tampa Bay Lightning, the NHL’s best team, without forward Jaden Schwartz and defensemen Alex Pietrangelo and Jay Bouwmeester was too much to overcome. It would’ve been easy to blame their 3-0 loss at Scottrade Center on Tuesday to those injuries. They were missing Schwartz’s firepower (35 points) and Pietrangelo’s and Bouwmeester’s leadership and minutes (25:45 a night for Pietrangelo, 18:18 for Bouwmeester). But missed opportunities were what hurt the most.