TEMPE, Ariz. — The blueprint worked in 2002, when the Angels won a World Series title with a competent but hardly overpowering rotation and a deep and dominant bullpen led by Troy Percival, Brendan Donnelly and Francisco Rodriguez.
It would be unfair to expect a similar relief effort from Ernesto Frieri, Joe Smith, Sean Burnett, Dane De La Rosa et al, but the Angels might lean as heavily on their bullpen this season as they did in 2002.
Jered Weaver, who has thrown 200 innings or more in three of the last five years, is an established ace, and C.J. Wilson, who surpassed 200 innings in each of the last four years, is a solid No. 2 starter.
Beyond them in the projected rotation are three youngsters with plenty of potential but little in the way of track records.
Garrett Richards, 25, solidified a spot by going 5-4 with a 3.72 earned-run average in his last 13 starts of 2013, but the right-hander hasn't thrown more than 157 innings in any of the last three seasons.
Hector Santiago, 26, has a vast repertoire that includes a 93-mph fastball, screwball and changeup, but the former Chicago White Sox left-hander has been a big league starter for one season and has not thrown more than 149 innings in the last three years.
Tyler Skaggs, 22, touched the big leagues with Arizona in 2012 and 2013, but his 1581/3 innings in the minor leagues in 2011 were the most he's thrown in three years.
"There's no doubt the depth of our bullpen is going to be more important for several reasons — one that our young pitchers haven't had the full 200-inning [workload] of a major league season," said Manager Mike Scioscia. "Everyone has to be really functional in our bullpen to hold leads."
Starters averaged just under six innings and relievers just over three innings a game last season. The fewer innings the starters throw, the more stress it puts on the bullpen.
The Angels for several years have had a two-tiered bullpen, with three or four arms trusted to hold leads and three or four used almost exclusively in games the Angels trailed. They'll need six or seven front-line relievers this season.
"If a starter goes deep, you have two guys to pitch the eighth and ninth innings, but there are games you have to battle to win, when the starter goes five," said Smith, the sidearm-throwing setup man who left Cleveland to sign a three-year, $15.75-million deal with the Angels.
"We need guys to step up in those situations, throw up zeros, keep us in the game and pass the ball to the next guy. It doesn't matter when you're pitching, you have to get outs and let offense do what it's going to do."
The Angels bolstered a thin and wobbly bullpen that combined to go 20-27 with a 4.12 ERA — 13th best in the American League — last season, and they could get a huge boost if Burnett recovers from an elbow injury that limited the veteran left-hander to 13 games in 2013.
Frieri converted 37 of 41 save opportunities and used his lively 95-mph fastball to strike out 98 in 682/3 innings last season.
Smith has been durable and dependable, with a 16-9 record and 2.42 ERA in 213 games over three seasons in which he's held left-handers to a .203 average. His funky delivery adds diversity to a bullpen filled with hard-throwing right-handers.
De La Rosa had a breakout 2013, going 6-1 with a 2.86 ERA in 75 games, and Kevin Jepsen is fully recovered from an appendectomy that ended his season last August.
There are two more hard-throwing right-handers in Michael Kohn, who had a 3.74 ERA in 63 games last season, and Fernando Salas, who had a 2.28 ERA and 24 saves for St. Louis in 2011.
Rule 5 pick Brian Moran and veteran Clay Rapada will compete for left-handed specialist roles, and veteran right-hander Brandon Lyon, who has a 4.16 ERA in 12 seasons, is on a minor league deal.
"I know we have some young starters — I've seen them, and they can pitch," Frieri said. "But if they need help, we have a great bullpen that can go in early or late and do the job."
Jepsen has been with the Angels since 2008 and sees a common thread to hot streaks. "When we go on rolls, the bullpen is usually dominant," he said.
But it's hard to sustain winning streaks without a stockpile of quality relief arms.
"Bullpen depth is huge," Smith said. "You can't pitch every single day. You need seven guys who want the ball and can pitch in any situation."
Twitter: @MikeDiGiovannaCopyright © 2015, Los Angeles Times