8:05pm: The Red Sox, too, are interested in Frasor, a source tells WEEI.com’s John Tomase. The Sox are currently sorting through options to improve a bullpen that has lacked reliable options behind Koji Uehara and Junichi Tazawa, Tomase notes, and Frasor is among the considerations.

5:08pm: The Mariners are “taking a hard look” at right-hander Jason Frasor, according to Bob Dutton of the Tacoma News Tribune. Frasor became a free agent earlier this week after he was designated for assignment by the Royals and opted for free agency.

As Dutton writes, manager Lloyd McClendon recently expressed displeasure with the performance of his team’s right-handed relievers. McClendon noted that much attention is paid to the club’s anemic offense, but the team had offensive struggles in 2014 as well. A lack of quality right-handed relief options, in McClendon’s estimation, has been a significant detriment to the team’s success. “In my opinion, the biggest disappointment to date has been the right-handers we’ve had to shift in and out of our bullpen to try to bridge the gap,” said McClendon.

Seattle has indeed seen its shares of struggles in the bullpen. Danny Farquhar, Tom Wilhelmsen, Yoervis Medina and Dominic Leone were standout performers in 2014, but neither has performed well in 2015. The 28-year-old Farquhar’s velocity and strikeout rates have plummeted, while his walk and home run rates have both soared. The result has been a 6.23 ERA — more than three full runs higher than his 2.66 mark from 2015. Wilhelmsen’s ERA has more than doubled, though it’s at least worth noting that his strikeout and walk rates have improved; he, however, has been plagued by a BABIP north of .400 and a fluky strand rate. Medina and Leone have both been traded this season after their own struggles. None of the four is presently in the Major Leagues.

Also of note regarding the Mariners’ bullpen struggles is the collapse of 2014 closer Fernando Rodney. The veteran has long had control issues, but in his best years they’ve been masked somewhat by a hefty strikeout rate. That hasn’t been the case for Rodney this season, as he’s posted a dreadful 5.50 ERA with just 7.0 K/9 against 4.3 BB/9. The 38-year-old has also been more homer-prone than usual.

Overall, the Mariners have received a collective 3.81 ERA from their bullpen, which ranks just 22nd in the Majors. Sabermetrics don’t paint any rosier of a picture, as FIP (3.81), xFIP (3.85) and SIERA (3.54) all feel that the production has been mediocre, at best, relative to the rest of the bullpens in the league. Rookie Carson Smith, journeyman Mark Lowe and lefties Joe Beimel and Charlie Furbush, however, have delivered strong to excellent bottom-line results.

Of course, Frasor would hardly represent a guaranteed cure for the Mariners’ bullpen troubles. Although the 37-year-old worked to an excellent 1.54 ERA in 23 1/3 innings with the Royals, he also issued 15 walks (13 unintentional) in that time and posted the lowest K/9 rate (6.9) of his career. Additionally, given his track record, one would imagine that there will be a number of clubs to show interest in the veteran right-hander, whose brush with midseason free agency seems unlikely to be lengthy in nature.