The right-hander has converted his last 12 save opportunities, dating to May 2 at Cincinnati.
"It's all confidence now," Sveum said. "It's confidence in being able to throw his fastball to get the swings and misses now, and guys aren't just waiting for a slider. The velocity, throwing strikes, getting back in counts, now he's gotten more swings and misses on strikes. His confidence has to be on a high level."
If Marmol's velocity appears to be increased, it's not that he's doing extra arm strengthening exercises.
"He's always had [velocity]," Sveum said. "Before, he didn't want to throw his fastball for a strike so he wouldn't air it out."
But wouldn't Sveum like an easy ninth?
"He's done the job," Sveum said. "You look at every closer, every night, no matter if the guy is throwing more strikes or whatever, the winning run is going to get to the plate. That's just the way it is. One-two-three innings in the last couple innings are difficult to find. I don't care if the guy on the mound never throws balls at all -- he's going to give up a hit. That's just the way it is."