The Giants added two front-line starting pitchers in free agency.
Their lineup is considered one of the best in baseball.
What about the bullpen?
"That's the No. 1 question.," Mike Krukow said on KNBR 680 on Monday morning. "You lose a component like Jeremy Affeldt, who has been an amazing contributor to that bullpen for the longest time ... a guy like that is difficult to replace and I'm anxious to see how they're gonna do it."
From 2009 to 2014, Affeldt racked up a 2.76 ERA over 362 appearances.
He was even better over the 2010, 2012 and 2014 postseasons -- 26 innings, two earned runs for a 0.69 ERA.
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But in 2015, he went 2-2 with a 5.86 ERA.
Who might replace him?
"Josh Osich, last year, really put himself in the mix and got everybody excited," Krukow explained. "He was healthy really for the first time in his professional career. We need him to be healthy. We need him to pick up where he left off last year.
"And I think there will be some opportunity for some of the younger arms. The Giants have some really good arms in their minor league system. Most of them are bullpen guys, and you're gonna see a lot of really high velocity stuff arms this spring from young guys. I think that's gonna be very interesting to watch."
The Giants selected Osich in the sixth round of the 2011 draft. He made his big-league debut last season and went 2-0 with a 2.20 ERA over 35 outings.
Sergio Romo, Hunter Strickland, Javier Lopez, George Kontos and Santiago Casilla are all back and all posted ERAs below 3.00 last season.
The goal is for Bruce Bochy to not call upon those guys very often, and have the starters pitch deep into games.
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"You have the potential to have five guys that go 200 plus with their inning count," Krukow declared. "And if that's the case, it's going to take a lot of pressure off the bullpen, even to the point where you might not need to have 12 bullpeners You might go with 11 if your starters are eating up that many innings, which gives you another option off the bench with an extra player."
Madison Bumgarner has thrown over 200 innings in five straight seasons.
Johnny Cueto has tossed 200 plus in three of the last four seasons.
Jeff Samardzija has gone over 200 innings three straight years.
After two injury-plagued seasons, Matt Cain is healthy and aiming to be the pitcher that threw over 200 innings six straight years from 2007 to 2012.
Jake Peavy logged 202.2 innings in 2014.
"Innings-eaters are so important," Krukow emphasized. "For the longest time, everybody has been saying if you get two 200 plus guys in your staff, you're lucky. But now, the Giants will realistically have a chance to get four or five ... the potential is there."