Injuries have slowed the Mariners early this season, but the club's bullpen has emerged as a major source of stability.
Seattle's relief corps owns the best bullpen ERA (1.29) in baseball since May 22, and its stellar performance continued over the past week. As a result, the Mariners secured the honor of "Bullpen of the Week presented by The Hartford" for June 5-11.
As part of the MLB Prevailing Moments program, each Monday throughout the 2017 season, MLB.com is honoring the "Bullpen of the Week presented by The Hartford." An industry-wide panel of MLB experts, including legendary stats guru Bill James, constructed a metric based on James' widely renowned game-score formula, to provide a weekly measurement of team-bullpen performance.
:: Bullpen of the Week winners ::
Here's how the Bullpen Rating System is compiled for each week. For reference, a weekly score of 100 is considered outstanding:
• Add 1.5 points for each out recorded
• Add 1.5 points for each strikeout
• Add 5 points for a save
• Subtract 2 points for each hit allowed
• Subtract 4 points for each earned run
• Subtract 2 points for each unearned run
• Subtract 1 point for each walk
• Subtract 5 points for a blown save
Seattle's bullpen scored 87 points in the past week, allowing just two earned runs on 16 hits over 20 2/3 innings. Mariners relievers struck out 22 with just four walks and converted their lone save chance.

Five bullpen arms threw at least two scoreless innings for the club, with Dan Altavilla, Emilio Pagan, Edwin Diaz, James Pazos and Nick Vincent combining to toss 14 spotless frames. Altavilla led the team with five innings, and Pagan didn't allow a hit in his four innings -- all of which came in Sunday's loss to the Blue Jays.
The unexpected: The Mariners fell behind within the first five innings in five of their six games this past week, so the bullpen was consistently tasked with keeping the game in reach as the offense attempted to fight back. Two of the club's three wins were come-from-behind affairs set up by stellar relief work.
How they prevailed: With the Mariners down, 5-4, vs. the Twins on Wednesday heading into the eighth inning, Pazos and Diaz threw a scoreless inning each, giving Mike Zunino the opportunity to belt a walk-off homer in the bottom of the ninth. The bullpen was handed another one-run deficit two days later and held it there as Tyler Cloyd, Vincent and Diaz combined to blank Toronto over three innings. Seattle took the lead in the bottom of the seventh, scored another run in the eighth and went on to defeat the Jays, 4-2.
The Mariners barely eked out the win for top bullpen honors, besting the second-place Rockies (86 points) and third-place Cubs (85.5 points).