In the last three seasons with the Astros, Lopez, 29, has gone 13-11 with a 2.64 ERA in 205 games. Lopez, a first-year arbitration-eligible player this winter, struck out 160 and walked just 31 in 204 1/3 innings in that span.
Lopez took over as Houston's closer late last year when Brett Myers was traded to Chicago and veteran Francisco Cordero struggled. Lopez had a 2.17 ERA and struck out 54 batters while walking eight in 66 1/3 innings in 64 games in 2012.
Along with adding a centerfielder, the Phillies are in need of a veteran eighth-inning arm to bolster a mostly young bullpen. Last season, Phils pitchers had a 3.85 ERA from the seventh inning on; only nine teams in baseball had a higher ERA.
As team policy, the Phillies do not comment on trade rumors or trades until there are completed.
In addition to seeing the deal with Houston fall through, the Phils watched as two of their division rivals acquired new centerfielders in the last 2 days.
On Wednesday, the Atlanta Braves reached an agreement with longtime Tampa Bay outfielder B.J. Upton on a 5-year, $75.25 million contract. The Phils were also interested in Upton, but a report on the Braves website said their top offer came in at 5 years and $55 million.
On Thursday, the defending division champion Washington Nationals traded pitching prospect Alex Meyer to the Minnesota Twins for Denard Span. Span, 28, hit .283 with a .342 on-base percentage and 17 stolen bases in 128 games with the Twins in 2012.
Another bullpen option also vanished when Ryan Madson finalized an incentive laden, 1-year deal with the Los Angeles Angels. The Phils were interested in reuniting with Madson, who spent 2012 recovering from Tommy John surgery, but the 32-year-old was seeking a closer job this winter.
The Phillies at least can take solace in the fact that this early in the offseason, there are still plenty of players looking for work.
Among the free-agent centerfielders still available are Michael Bourn, Josh Hamilton, Shane Victorino and Angel Pagan. Mike Adams, Brandon Lyon and Myers are among relievers with setup experience on the open market.
The Phils, of course, also could look to fill either or both holes via trade. The Winter Meetings begin on Monday in Nashville.
Major league teams have until midnight - or technically, 11:59 p.m. Friday - to tender contracts to arbitration eligible players. The Phillies have just two: reliever Antonio Bastardo and outfielder Nate Schierholtz.
There is at least the possibility that the Phillies will non-tender Schierholtz, 28. He hit .257 with a .728 OPS and six home runs in 114 games between Philadelphia and San Francisco in 2012. He played in only 37 games with the Phillies while dealing with a foot injury.
Acquired in the trade that sent Hunter Pence to the Giants, Schierholtz made $1.3 million in 2012. If he is non-tendered, Schierholtz would become a free agent.
While the Phils have been trying to upgrade their outfield this winter, lefthanded hitters Domonic Brown and Laynce Nix and righthanders John Mayberry Jr. and Darin Ruf all figure to return in 2013.
On Twitter: @ryanlawrence21