They're left today with Weaver, Wilson and who knows what?
Santana is now with the Royals, and Greinke and Haren are free agents, likely to be treated as royalty by clubs in need of quality starting pitching. That takes in virtually the entire landscape.
Angels manager Mike Scioscia has always maintained that the foundation of every team is its rotation. With the Santana swap and the decision to buy out Haren's option for 2013, the Angels' foundation has obvious cracks in need of patching. What the Angels have in mind to address this matter is anybody's guess.
They love Garrett Richards' arm, and Jerome Williams is a viable candidate. Veteran southpaw Brad Mills also could be in the picture. Just getting started, promising lefty Nick Maronde excelled in a relief role late in the season for Scioscia and has a starter's repertoire. But he probably needs another year to develop.
Weaver is one of the best and Wilson is solid, but in its current form, this is not a rotation that would concern the Rangers, who won the American League West in 2010-11 and earned a Wild Card berth in '12. Or, for that matter, the upwardly mobile Athletics, the surprise AL West champions last season.
Greinke obviously is the Angels' highest priority now. They've cut significant payroll in dealing Santana, cutting loose Haren and not offering a one-year, $13.3 million deal to keep Torii Hunter -- their leader for five seasons -- out of free agency.
Greinke, a premium performer in his prime, is sitting on a gold mine as the most valuable arm in the open market. The bidding will go sky high. Yet, as talented as he is, Greinke is not as good as Weaver.
How in good faith can you justify spending perhaps $30-35 million more on Greinke, your second starter, than your ace and staff leader will earn over a five-year period?
Weaver knew what he was doing when he signed that team-friendly, five-year, $85 million extension, and he says it wouldn't bother him if Greinke, as a free agent, drew a bigger deal. But you'd have to wonder. He's a team guy to the bone, but Weaver is also human.
There are other routes to explore, but it's doubtful the Angels have the resources to acquire a top-shelf starter in a trade. Most of their prime young pitching talent (Tyler Skaggs, Patrick Corbin, Johnny Hellweg) has been detached the past few seasons in the deals for Haren and Greinke.
That leaves a free-agency pool that is relatively deep with mid-rotation types, which might get it done, given the explosive offense the Angels have assembled.
Having shed the salaries of Hunter, Haren, Santana and Bobby Abreu, with Maicer Izturis and LaTroy Hawkins headed for free agency, general manager Jerry Dipoto appears to be in position to land a couple of quality arms in free agency.
The problem is, the demand for pitching is such that the price tags figure to be relatively high for such sturdy veterans as Hiroki Kuroda, Anibal Sanchez, Kyle Lohse, Ryan Dempster, Brandon McCarthy, Shaun Marcum, Jeremy Guthrie and Edwin Jackson.
Kuroda, who was 16-11 with a 3.32 ERA for the Yankees this season, is the best of the bunch. It is believed he favors the West Coast from his four years with the Dodgers.
For dollar value, the tough, tested Kuroda actually might be a better short-term investment than Greinke. The hitch is that Kuroda will pitch at 38 in 2013, Greinke at 29.
As for the always-concerning Angels bullpen, an intriguing name to consider is Ryan Madson. A successful closer with the Phillies in 2011 after seven seasons as a setup man, he moved to the Reds as a free agent in 2012 and missed the entire season with Tommy John surgery.
Madson, 32, is a Southern Californian and could emerge as a hammer again around midseason if he's handled with care.
The Angels' 2012 payroll of $159 million was the fourth highest in the Majors, thanks largely to the blockbuster signings last winter of Wilson and Albert Pujols and the midseason acquisition of Greinke.
There are no glaring needs on the field if management is satisfied with what Alberto Callaspo -- a contact hitter with limited power and speed and average defense -- has to offer at third base.
Hank Conger is expected to be given a shot at backing up Chris Iannetta behind the plate with the departure of Bobby Wilson. Conger, a switch-hitter long held in high regard, has the ability to bring a much needed left-handed power source to the lineup.
In Hunter's anticipated absence, Peter Bourjos -- a high-quality center fielder and emerging offensive weapon in 2011 -- will be given an opportunity to reestablish that his extraordinary speed and talent translate into something special in a youthful unit alongside all-universe Mike Trout and powerful Mark Trumbo.
Lyle Spencer is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.