SEATTLE -- Less than 24 hours after the Astros blew a seven-run lead in Monday's loss to the Mariners, when All-Star closer Ryan Pressly was unavailable to pitch, the club upgraded its bullpen. Houston landed right-handed relievers Kendall Graveman and Rafael Montero from Seattle on Tuesday in exchange for reliever Joe Smith and infielder Abraham Toro.

Graveman is the key piece for the Astros, whose efforts to upgrade their bullpen have been going on long before Monday’s stinging loss. The 30-year-old Graveman was one of the best relievers on the market this year, as he posted a 0.82 ERA in 30 games for the Mariners and recorded 10 saves. Entering Tuesday, he owned the lowest WHIP (0.70) among all Major League relievers and the lowest ERA, opponent batting average (.136) and opponent OPS (.424) among all AL relievers.

Astros get: RHP Kendall Graveman, RHP Rafael Montero
Mariners get: INF Abraham Toro, RHP Joe Smith

“We were very impressed with him,” Astros general manager James Click said of Graveman. “We’ve obviously seen him up close and personal. He’s a guy that I know our hitters in our clubhouse have been very impressed with, and being able to have him on our side is something we’re all looking forward to. What impact he can have with his ability to get big outs and sort of lengthen our bullpen a little bit, I think, is one critical step in the right direction as we try to round out the rest of the roster.”

Graveman, who simply had to head over to the other clubhouse at T-Mobile Park with the Astros in town, will join Pressly in the back end of Houston’s bullpen. Astros manager Dusty Baker said Pressly will remain the closer, but Graveman gives them another proven arm. Houston’s bullpen entered Tuesday ranked 15th in the Majors with a 4.15 ERA and 22nd with a 4.36 FIP.

“It gives us a couple of guys that have both closed and pitched in high-leverage situations at the end of the game, and it gives us some more quality firepower and gas in the bullpen to go with what we have now,” Baker said. “We’re happy about it. We hate to see Joe Smith go, because he’s a big part of this team and a big part of the bullpen and one of the highest-quality people I’ve ever met. And Toro has a bright future and was coming on pretty strong and had helped us during [starting third baseman Alex] Bregman’s absence [with a left quad injury].”

Click hinted the Astros might not be done dealing before Friday’s 3 p.m. CT Trade Deadline.

“It’s a move that we feel improves our roster, but we are going to continue to spend the next three days finding, hopefully, additional moves to improve the roster,” Click said. “We are going to overturn every rock, look under everything we possibly can, to continue to put these guys in position to compete for a World Series.”

Graveman, who’s a free agent after the 2021 season, said he was shocked to be traded by a Mariners team that’s making a push for its first postseason berth in 20 years, but he is thrilled to join the Astros. Graveman was a starter with the A's from 2015-18, before moving to the bullpen when he signed with the Mariners prior to the 2020 season.

After missing time due to a benign tumor in his neck in '20, Graveman was converted to a reliever last September and has flourished with a sinker that hits 96 mph.

“I understand the business of this game,” Graveman said. “I understand how things can happen quickly. I was a little bit shocked, to be honest. I’m excited to put on this jersey. I’ve competed against this team for a long time. I know the talent that’s on this team. It’s exciting to lock arms with them for the last two months and beyond.”

Montero, acquired by Seattle in a trade with Texas last December, began the season as the Mariners’ closer, but he lost the job. He has a 7.27 ERA in 40 appearances this year, allowing 56 hits in 43 1/3 innings. He was designated for assignment last Friday and will join Houston’s bullpen on Wednesday.

A seven-year veteran, Montero has spent time with the Mets (2014-17), Rangers (2019-20) and Mariners (2021). He is under club control through the 2022 season

“This is a guy who has a track record of being very successful,” Click said. “Certainly his ERA is not what I’m sure he would like it to be this year, but he has the ability to get big outs at the end of the game and it’s something we hope to continue to work with him on, and we think he’s going to be a big part of this team moving forward.”