Angels open camp with familiar script

TEMPE, Ariz. -- There is high anticipation surrounding the Angels as pitchers and catchers report to spring training Monday, the team’s surprising December addition of baseball’s top free-agent slugger boosting its World Series hopes.

Wait, haven’t we seen this before?

Yes, the names have changed, Josh Hamilton replacing Albert Pujols as the off-season acquisition, but the theme entering 2013 is the same as 2012: The Angels, with a powerful lineup and stellar defense, are built to win the World Series, and anything short of a deep playoff run would be a disappointment.

These things don’t always follow script, though. The Angels stumbled badly last April and spent three months climbing back into the American League West race before another slump in August cost them a playoff spot.

Having dynamic leadoff man Mike Trout for the first month — the 21-year-old phenom didn’t join the Angels until last April 28 — could prevent a slow start, but if the Angels are to live up to their lofty expectations, they’ll need better starting and relief pitching than they got in 2012.

Among the story lines to watch this spring:

As the rotation turns

General Manager Jerry Dipoto received some praise for replacing Dan Haren and Ervin Santana, who combined for a 21-26 record and 4.75 earned-run average in 355 innings in 2012, with Joe Blanton and Tommy Hanson, who had a 23-23 record and 4.60 ERA in 366 innings, for less than half the cost.

True, their production was comparable, while their pay — Blanton and Hanson will be paid $10.25 million combined this season; Haren and Santana were paid $24 million last season — is not.

But that reasoning is flawed because neither Haren nor Santana, who gave up a major league-leading 39 home runs, was very good in 2012, and replacing them with equal pitchers doesn’t improve the rotation. Plus, Blanton and Hanson could suffer from the switch from the pitcher-friendly National League to the less-forgiving AL.

A more shrewd move for Dipoto was acquiring Jason Vargas from Seattle. The left-hander is not as dominant as Zack Greinke, but he has solid numbers — a 14-11 record, 3.85 ERA, 141 strikeouts and 55 walks in 217 innings.

Swing man

The effectiveness of the bullpen, which tied for the AL lead with 22 blown saves last season, could hinge on how Ryan Madson rebounds from Tommy John surgery. The right-hander, who sat out 2012, is on a schedule that is targeting mid-April for his return.

If the former Philadelphia closer regains his 2011 form, when he had a 4-2 record and 2.37 ERA with 32 saves in 34 chances, he’ll provide a back-end hammer to a group that includes hard-throwing right-handers Ernesto Frieri and Kevin Jepsen and veteran left-handers Scott Downs and Sean Burnett.

If not, the Angels could suffer from the same bullpen depth issues that plagued them last season.

Reasons for optimism

What’s not to like about this lineup? Leading off is Trout, the 2012 rookie of the year and runner-up for most valuable player who hit .326 with 30 home runs, 27 doubles, 83 runs batted in, 129 runs and 49 stolen bases.

In the middle are Pujols, Hamilton and Mark Trumbo, who combined for 105 home runs, 100 doubles and 328 RBIs last season. There is more speed and situational hitting (Erick Aybar, Peter Bourjos), gap power (Howie Kendrick, Alberto Callaspo) and on-base ability (Chris Iannetta).

With Bourjos in center field, Trout in left and Hamilton in right, the Angels should have one of baseball’s best defensive outfields. The infield is solid as well.

Reasons for skepticism

After ace Jered Weaver, there are rotation questions: Will C.J. Wilson rebound from surgery to remove bone spurs in his elbow and pitch more like he did in the first half (9-5, 2.43 ERA) than the second half (4-5, 5.54 ERA) last season?

Can Hanson, the former Atlanta right-hander who has been slowed by shoulder and back injuries, reverse a trend in which his ERA rose from 3.33 in 2010 to 3.60 in 2011 to 4.48 in 2012, and his average fastball velocity in those years dropped from 92.7 mph to 91.2 to 89.7?

Can Blanton, the former Philadelphia and Dodgers right-hander who had a 4.51 ERA in five NL seasons and gave up 27 home runs or more in each of his last three full seasons, be effective enough in the rugged AL to keep the Angels in games?

And were those 35 home runs — second-most in baseball — Vargas gave up last season a fluke or reason for concern?

mike.digiovanna@latimes.com

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