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June 29: Mets 'all but guaranteed' to trade for bullpen help
Tuesday's 9-1 loss to the Astros showed that the Mets could be well-served to improve their offense, starting pitching and/or bullpen prior to the Aug. 2 Trade Deadline. MLB.com's Anthony DiComo assigned an "upgrade urgency" label -- low, medium or high -- to each of these three areas Wednesday.

The bullpen was tagged with the highest urgency. The Mets relievers have posted a 4.00 ERA this month, and DiComo wrote that the 'pen is "one area in which the Mets are all but guaranteed to make a splash given the lackluster performances of nearly everyone other than closer Edwin Díaz."

With left-landers Chasen Shreve and Joely Rodríguez sporting a combined 5.73 ERA, DiComo lists three southpaws who could potentially be available in a deal for the Mets: The Tigers' Andrew Chafin and Gregory Soto, and the Orioles' Cionel Pérez.

Chafin, who signed a two-year deal with Detroit in March, got off to a late start this season due to an injury and has seen his ERA jump up by more than a full run from his 1.83 last year. However, Chafin has a 2.47 expected ERA and a 2.20 FIP. His 23.8% strikeout-minus-walk rate is the best of his career, and he's limiting left-handed batters to a .176 average.

Soto, the Tigers' flamethrowing closer, has notched 14 saves in 16 chances and has a 2.76 ERA. But his expected ERA is nearly two runs higher, thanks in part to an average exit velocity of 93.4 mph, which is the fourth highest among all pitchers with at least 50 batted balls this season.

Pérez, whom the Orioles claimed off waivers last November, has pitched to a 1.52 ERA through 23 2/3 innings. However, that's been helped by an extremely high 92.5% left-on-base rate. The 26-year-old has also allowed a fair amount of hard contact and has a WHIP of 1.48, so his expected ERA is 5.12.

June 24: Mets have 'checked in' on Castillo (report)
The Mets have maintained their place atop the NL East standings despite several injuries to key starting pitchers, including Jacob deGrom and Max Scherzer. According to MLB Network insider Jon Heyman in an article for The New York Post, the club has "checked in" with the Reds on the availability of right-hander Luis Castillo in a potential trade. Heyman also lists another Reds righty, Tyler Mahle, as well as A's right-hander Frankie Montas, as potential targets for New York. Heyman adds that the Mets will be looking at upgrading both the lineup and the bullpen, as well.

June 7: Mets scouting veteran closer Rosenthal
Mets relievers have recorded the second-most strikeouts in baseball this year, and the team ranks seventh in bullpen ERA. And they could be looking to add to this strength. According to SNY's Andy Martino, the Mets were one of the teams in attendance for Trevor Rosenthal's showcase today in Miami. The former All-Star reliever hasn't pitched in the Majors since 2020 due to shoulder and hip injuries.

Rosenthal, 32, reportedly topped out at 96 mph during the showcase, which is a couple of ticks down from his average fastball when he was last on a Major League mound. He posted a 1.90 ERA and locked down 11 of 12 save opportunities across 23 2/3 innings that season split between the Royals and the Padres. He parlayed his successful season into a one-year, $11 million contract with the A's in February 2021, but he never pitched for Oakland as it was announced in April that he needed thoracic outlet surgery. In July, Rosenthal underwent season-ending hip surgery to fix a torn labrum.

The hard-throwing Rosenthal was a star at the back of the Cardinals' bullpen early in his career. From his debut 2012 season through 2015, he recorded a 2.66 ERA and struck out 303 batters in 237 innings. He saved 45 games in 2014 and 48 more during his 2015 All-Star campaign.

But Rosenthal's effectiveness declined from there as injuries began to take their toll. He underwent Tommy John surgery in 2017 -- his last year in St. Louis -- and missed all of the following season as he rehabilitated.

Following forgettable short stints with the Nationals and Tigers, Rosenthal latched on with Kansas City prior to the '20 season. He finished that year with a 33.0 strikeout-minus walk rate and Statcast metrics that were among the best in the Majors. Batters hit just .154 off of his fastball, which produced a 35 percent whiff rate.