Jerry Dipoto's roster blind spot is threatening to destroy the Mariners' season

Seattle Mariners president of baseball operations Jerry Dipoto has proven himself as a masterful drafter, and has emerged as one of the MLB's most aggresive team-builders when it comes to making trades. However, he has a significant blind spot that is hurting the Mariners once again this year.

Dipoto has seemingly no idea how to fill out the bench.

Let's go back to the beginning of the season. On Opening Day, the Mariners' bench consisted of backup catcher Mitch Garver, platoon first baseman Donovan Solano, and two utilitymen in Dylan Moore and Miles Mastrobuoni.

Theoretically, Garver would backup Cal Raleigh, Solano would platoon with Rowdy Tellez, and the utilitymen would fill in to give rest days to the rest of the team.

To his credit, Garver and Solano did fill their roles. Moore, however, quickly was asked to fill in at second base for Ryan Bliss, which he did well until May 27th when he fell off a statistical cliff and finally earned a ticket off the roster in August. Mastrobuoni was almost exclusively utilized as a third baseman, but he also struggled to make an impact.

That left the outfield depth and middle infield incredibly thin, and it's beginning to show in the final weeks of the season.

Depth issues are catching up to the Mariners in September

Cal Raleigh has started in 136 of the team's 141 games (104 at catcher), J.P. Crawford has started in 135 at shortstop, Julio Rodríguez has started 139 games (138 at center field) and Randy Arozarena has started 139 (137 in left field).

Then there are Josh Naylor and Eugenio Suárez, who the team added at the deadline. Naylor has started 34 of 38 games since the trade, while Suarez has started all 32 games since his trade to Seattle.

Even the back end of the lineup has been playing almost every day as of late. Jorge Polanco has started 39 of the team's last 43 games. Dominic Canzone has started 57 of 76 games since being called up from Tacoma, and Cole Young as started 65 of 84 games since his own call-up.

Canzone and Young have been getting some rest, but everyone else is playing just about every day. It's worth wondering if Seattle could utilize it's bench better to get their regular's more rest.

Ryan Divish recently wrote in the Seattle Times that Seattle's regulars might be getting worn out. It's certainly possible. Crawford, Arozarena, Suárez and Naylor are all slumping as the summer draws to an end. It could be they are all getting unlucky at the same time, or it could be that they are getting tired.

Even Raleigh, despite his MLB leading 51 home runs, has not been the same since the All-Star break.
His .750 OPS in the second half is not close to the 1.011 mark he held before the break.

Arozarena's slump has not been for as long or as bad, but he still has struggled over the past month-and-a-half. Since July 20th, the All-Star left fielder has a .663 OPS and .205 batting average.

Then there's Naylor, who came to the Mariners scorching hot. Since August 12th, he's slashing .216/.237/.284, for a .521 OPS. Notably, during that 20-game stretch, the first baseman has hit just one home run and stolen one base. Suárez has also struggled since being traded to the Mariners, posting a .188 average and .643 OPS.

Again, there is no hard evidence that the reason everyone is slumping at the end of the year is their lack of rest. It's purely speculation. But what are the odds that five of the Mariners' six most heavily used hitters would see their offensive production slow down in August and September?

If the Mariners had a more capable bench, perhaps they wouldn't be having these issues. As it is, Garver is the only one left from the Opening Day bench. Luke Raley and Victor Robles are also there after having been demoted from starting roles after spending much of the year on the IL, and neither has made an impact lately. Robles will return from a suspension on Saturday. Raley has a .205 OPS in his past 13 games, making him just about unplayable.

What makes the bench even more questionable now is the addition of Harry Ford. Ford, a catcher, has yet to start a game for Seattle and offers no additional defensive value. His spot on the roster might make more sense being given to somebody like Samad Taylor, who could play any position and give the regular starters a few more offdays down the stretch.

Then again, is the team able to afford giving their starters rest? With their lead in the AL Wild Card chase dwindling with every passing day, it feels like the best possible lineup needs to be playing every given night.