BOSTON -- With his roster as young as it is, Marlins manager Don Mattingly has to find the silver linings where he can.
Take Tuesday's eighth inning, for example. Yes, rookie reliever Tayron Guerrero squandered a 6-4 lead in a game the Marlins eventually lost in walk-off fashion to the Red Sox in the ninth. But to Mattingly, Guerrero didn't just hand the game over with free passes, the way he has at times earlier this season. He attacked the loaded Boston lineup. He just didn't come out on top.
It was just another learning experience for a young pitcher who has moved into a more prominent role since Miami traded Brad Ziegler to Arizona a month ago.
"Tayron had a bit of a rough outing last night, but [the Ziegler trade] has given a lot of experience, where he's grown through some spots," Mattingly said. "Even last night, they had to get their hits. He had the one wild pitch, but other than that, they got hits. And you just have to tip your hat -- as opposed to walking guys and looking like he's disoriented out there. He's been growing up."

Roster ready to expand
Mattingly doesn't expect a parade of reinforcements on Saturday, the first day the Marlins can expand their roster beyond 25 players. But he does expect to add a handful of players in the next week or so, as the Triple-A season comes to an end.
Rookie center fielder Lewis Brinson is expected to be activated on Saturday, ending a spell of nearly two months away from the Marlins due to a bruised hip. Veteran infielder Martin Prado might not be far behind him.
Mattingly declined to disclose whom the Marlins will promote from Triple-A after that team's season comes to an end on Monday, but he said he generally knows the names that are in the mix for a big league promotion.