PITCHERS AND catchers hold their first official workout in Clearwater on Thursday. Among the story lines will be the following:

1) How healthy is Cliff Lee?

It's the million dollar question. Actually, several million. 37.5 of them, to be exact.

Lee's contract guarantees him a $25 million salary this season and a $12.5 million buyout of a club option for 2016. And if he pitches 200 innings this season and is not on the disabled list at the end of the year, that option becomes guaranteed at $27.5 million.

Money isn't a huge concern for the Phillies, but it is an indication of what they have at stake in Lee's attempt to return from a flexor tendon strain that cost him most of the last 4 months of last season. Lee could become a serious trade chip in July if he is healthy and effective.

Before his first stint on the disabled list, Lee looked like the pitcher he has been since he signed with the Phillies before the 2011 season. In 10 starts, the lefty logged 68 innings, 61 strikeouts and just nine walks while posting a 3.18 ERA and 1.05 groundball-to-flyball ratio. This, after a three-year stretch in which he averaged 222 innings with a 2.80 ERA and tremendous rate stats (9.0 K/9, 1.4 BB/9, 0.9 HR/9).

At the same time, Lee is 36, and the end can come quick for pitchers. At 34, Roy Halladay pitched 233 2/3 innings with a 2.35 ERA, finishing second in the NL Cy Young voting. He would start just 38 more games, with a 5.15 ERA in 218 1/3 innings.

At this point, Lee has no trade value. And while you will hear plenty of talk of Lee needing to prove he is healthy, the only way he can do that is with time. And with the Phillies' determination to maximize their return in any trade, it seems unlikely that a deal would happen much earlier than the trade deadline.

2) What's up with Chad Billingsley?

It isn't every offseason that a team gives a guaranteed deal to a pitcher who has started just two games in 2 years. But the $1.5 million that the Phillies guaranteed the righthander is a decent investment because of the potential he has to pitch himself into becoming a trade asset. Make no mistake, it's a longshot that the Phillies will ever land anything of value for Billingsley. He missed all of last season and most of 2013 due to multiple elbow surgeries. And even during his prime he was more of a middle-of-the-rotation starter than a trade-deadline darling. That said, from 2007-12, Billingsley posted a 3.65 ERA while averaging 8.2 K/9, 3.6 BB/9 and 0.7 HR/9 for the Dodgers, and he is 7 months younger than Cole Hamels. Even without the potential of him becoming a trade chip, Billingsley will be an interesting individual story to monitor as he attempts to resurrect his career.

3) Where will David Buchanan slot in the rotation?

One year ago, Buchanan was a late addition to the spring training roster. He took advantage of the invitation, pitching himself into a regular role in the rotation for most of the season. Over his last 16 starts, the righthander posted a 3.16 ERA and a 1.27 groundball-to-flyball ratio. His lack of strikeout stuff is why he profiles as a back-of-the-rotation arm, but he'll have plenty of opportunities and could enter the season as the No. 3 starter, depending on how things shake out with Billingsley and righthanders Aaron Harang and Jerome Williams.

4) Is it Phillippe Aumont's last stand?

The lone remaining piece from the disastrous decision to trade Lee prior to the 2010 season, Aumont enters what could be his final spring as a member of the Phillies organization. The 26-year-old righthander is out of options, meaning he either makes the Opening Day roster or is exposed to waivers. In 45 major league appearances, Aumont has a 6.13 ERA and has walked an average of 6.1 batters per nine innings. He made just five appearances last year. That being said, the Phillies do have some room in their bullpen. Ken Giles, Jake Diekman and Justin De Fratus all have spots locked up. Jonathan Papelbon, barring a trade, also has one, and if Mario Hollands is healthy, he'll have the inside track on a spot. But that still leaves two open slots and more questions than answers. Along with Aumont, Cuban righty Miguel Alfredo Gonzalez and Rule 5 pick Andy Oliver will be vying for spots. If Billingsley ends up in the rotation, it would likely move Williams to one of the open bullpen spots. But with the Phillies still trying to trade Papelbon, it isn't inconceivable that Aumont makes the roster. First, though, he has to throw strikes.

On Twitter: @ByDavidMurphy
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