The club's offensive shortcomings of the last two years were addressed with Lee's massive six-year deal, and the addition of Williams gives the Astros a veteran presence to slide into the middle of the rotation. But the annual uncertainty of Roger Clemens' desire to return to the team, plus the added burden of Andy Pettitte joining his friend in the will-he-or-won't-he saga leaves the Astros in a position where they must try to obtain another workhorse to take over as the No. 2 starter behind ace Roy Oswalt.
Given the lucrative nature surrounding recent free agent signings, the Astros are more likely to seek starting pitching help through a trade rather than free agency.
The challenge is to find a team that matches up well with the Astros as trading partners.
"It's got to make sense for us," Purpura said. "You can talk to plenty of clubs, but you don't necessarily match up with them. Just because they're interested in your guys, there has to be a fit."
First and foremost, however, is the issue at third base. Purpura said his No. 1 priority is to figure out who will man the hot corner for the Astros next year, and he appears to have whittled his options to Morgan Ensberg or Mike Lamb, or both.
The club's interest in Aubrey Huff is "waning," according to Purpura, mainly because Huff will be seeking a three- or four-year deal worth more than the nearly $7 million per year Huff was earning at the end of his recent three-year contract that expired upon the conclusion of the '06 season.
Huff would fit well as the No. 5 or 6 hitter in a largely right-handed lineup, but he's average defensively and therefore may not be worth the high dollars he'll command.
Although Ensberg will make more than $4 million and Lamb is probably going to surprass the $2 million mark, platooning those two players at third base is a possibility.
"We're not quite in that territory where financial factors would come into play," Purpura said. "As we're configured now, we could probably handle those two."
However, that could change if Pettitte decides he wants to pitch in Houston in '07. Assuming Pettitte would command somewhere in the neighborhood of $10-12 million, that could severely cut into the payroll and force the Astros to rethink how they fill other areas of the roster.
Timing will be a factor. If Pettitte decides soon that he wants to rejoin the Astros, the Astros would most certainly fit him into a budget that could be as low as $85 million or as high as $100 million. If the left-hander's uncertainty continues further into the winter, the Astros will have no choice but to proceed as if he will not be in a Houston uniform next year. If it means spending the dollars allotted to Pettitte elsewhere, so be it.
"We're only going to have so much to spend," Purpura said.
Clemens would like be a mid-season addition, as he was last year, and therefore will not factor into the Astros' target Opening Day payroll.
Purpura probably won't tinker much with the bullpen, unless he can find a lefty to complement Trever Miller. It appears Purpura would like to retain the back end of the bullpen -- Chad Qualls, Dan Wheeler and Brad Lidge.
"I'm very satisfied with the bullpen," Purpura said. "That's one of challenges, to keep that intact. Everybody needs bullpen help. If we can find a lefty that would be preferable, for sure."
Alyson Footer is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.