In case you haven't noticed, the trade market for relief pitchers is moving fast. With Brad Hand and Adam Cimber having been dealt from San Diego to Cleveland and former Mets closer Jeurys Familia now a member of the A's, Zach Britton appears to be the biggest readily available bullpen piece. And the O's closer could be on the move soon.
In fact, a source told Patrick Mooney of The Athletic (subscription required) that the O's would like to conclude negotiations by the middle of this week.
A free agent this offseason, Britton missed the first two-plus months of 2018 while recovering from offseason surgery to repair a ruptured right Achilles tendon, but Britton's velocity and performance have picked up of late. The left-hander has allowed just three hits across eight scoreless innings since June 30 to lower his ERA to 3.45.
What's the latest chatter on Britton?

• The Cubs look like the favorite, according to MLB.com's Brittany Ghiroli, who pointed out Baltimore was looking to deal Britton soon after taking care of their blockbuster swap that sent star shortstop Manny Machado to the Dodgers last week. Ghiroli also indicates that the Astros, who wanted Britton last summer but couldn't finish a trade for him, shouldn't be dismissed. Meanwhile the Dodgers have interest, too, but they are concerned about adding the remainder of Britton's salary ($12 million this year) as they are bumping up against the Competitive Balance Tax threshold.
• MLB Network insider Jon Heyman echoes a lot of that, reporting Monday morning that the Astros and Cubs are at the front of the line for Britton, while suggesting that the Yankees are in the mix, as well.

• MLB.com's Mark Feinsand confirms Heyman's report that the Yankees are pursuing Britton, reporting that New York's interest is "real" on Monday. Feinsand also notes that as many as six teams could be vying for Britton.

• Dan Connolly of The Athletic (subscription required) also reports Monday that the Astros "appear to be the best fit" given their desire to improve their bullpen and their stock of pitching prospects the O's are known to covet.
• In his Monday column on nine trade targets who could make big impacts, MLB.com's Richard Justice puts the Braves as the top landing spot but also says the Astros make sense as they try to acquire Britton for the second straight summer.
• As for the Cubs, president of baseball operations Theo Epstein told SiriusXM radio host Craig Mish on Monday that, even in the wake of Brandon Morrow's trip to the DL for right biceps inflammation last week, the club might not be looking for a "replacement closer."

Considering Morrow's injury isn't expected to be serious, that could mean the Cubs' interest in Britton is more as another versatile late-inning option, potentially as a southpaw to mix in with the righty Morrow. It's also fair to wonder whether the Cubs have the resources to entice the O's after having traded away a number of their high-end prospects the past two summers, as Jesse Rogers of ESPN writes.
• In addition to the Astros, Cubs, Dodgers and Yankees, Heyman reported Sunday that the Braves, Rockies and Brewers also are in play. One key factor in any Britton talks, however, is just how serious a club like Atlanta is to acquire a rental player if it means giving up talent from its stacked farm system.

• Milwaukee's attempt to improve after missing out on Machado has the club continuing to "cast a wide net" for upgrades. Adding Britton to its deep, dynamic bullpen could be one approach, as MLB Network insider Ken Rosenthal reports.

• The D-backs -- another club whose farm system Baltimore is familiar with after having engaged in discussions for Machado -- also can be thrown into the Britton sweepstakes, Rosenthal points out.

• The Red Sox appear to be a potential landing spot for Britton, too, according to Roch Kubatko of MASNSports.com, who says the Astros and Cubs -- surprise, surprise -- have been very active in their pursuits.