"This game will humble you in a hurry," Thompson said. "Just when you think you've got it made up here, it can come back and bite you in a hurry and sometimes it bites you hard and long. He's kind of finding out a little bit about that right now.
"Even as confident as he was down below, he was confident up here earlier and he's lost a little bit of that. He's lost a little of his swagger. But he'll get it back. He's a young kid and it's part of the growing pains and learning situations he's going to have to go through."
Part of the learning curve is dealing with off-speed pitches, which have come with increased frequency as Franklin's struggles mount. He struck out the first three times in Thursday's 7-1 loss to the Rays, the third coming with the bases loaded on a 3-2 changeup by Alex Cobb.
"There were times through the entire game where he was just throwing me a lot of curveballs," Franklin said. "I was looking for that pitch before, and he threw me a changeup for a ball. I thought for sure he wouldn't throw it twice."
Welcome to the big leagues.
"When young guys get up here, you're going to be tested to see if you can hit a fastball," said Thompson. "If you can't, you're going to keep getting them. Well, he's a pretty good fastball hitter. Now all of the sudden, word gets out and they're throwing breaking balls in fastball counts and he has not really made that adjustment yet. That should come with time."
Franklin is hitting .242 with 10 home runs and 35 RBIs in 64 games, but is just 5-for-49 (.102) since July 31.
Greg Johns is a reporter for MLB.com. Follow him on Twitter @GregJohnsMLB as well as his Mariners Musings blog. This story was not subject to the approval of Major League Baseball or its clubs.