CHICAGO -- Scott Servais can't underestimate the value that Kyle Seager adds to his Seattle Mariners' lineup.

But take the power-hitting third baseman away like he has been for the past two games with a bruised foot and things change. It becomes increasingly more evident when the Mariners will face a full complement of left-handed pitchers over the next three games against the Chicago White Sox starting Friday when ace Chris Sale takes the mound.

Seager, who is hitting .286 with 24 home runs and 83 RBIs, hopes to return this weekend after fouling a pitch off his foot earlier this week. But considering the challenge the Mariners face Friday against Sale (15-6), Servais would rather have Seager back sooner than later.

So would Seager.

"I would have loved to play the last two days," Seager said after Thursday night's 7-6 loss to the White Sox.

Said Servais: "He's a key guy for in the middle of that line-up. We miss him when he's not in there."

Despite his 15 victories, Sale has been shaky of late, losing five of his last seven starts. But Sale allowed only three hits over eight innings Saturday against Oakland heading into Friday's start when he will face Felix Hernandez, who has won four straight starts.

While Servais continues to have to make his adjustments to content with Chicago's string of lefties that will include Jose Quintana on Saturday and Carlos Rodon on Sunday, he understands what kind of challenge Sale presents.

That's where Hernandez's ability to shut down opposing teams. Hernandez (8-4) hasn't allowed more than two runs in his past three starts, giving Servais some indication that Friday may be a low-scoring affair.

"(Sale's) one of the better pitchers in the league, but I think our guy (Hernandez) is one of the better pitchers in the league -- it should be a good game," Servais said.

While the Mariners remain in playoff contention, the White Sox continue to try to battle despite big offseason changes could be coming. General manager Rick Hahn said Thursday that he, executive vice president Kenny Williams and White Sox chairman Jerry Reinsdorf have a plan they will execute once of the offseason arrives.

Williams said earlier this week that the White Sox have got to "get some things together" as the regular season begins to wind down. But Hahn said that the top priority remains the present.

"Regardless of which direction it is -- full rebuild or add on --we're still in the middle of the season," Hahn said. "We have 25 guys in there trying to win a ballgame tonight. If I were to say we're going to do a full rebuild that's disrespectful to what they're trying to accomplish.

"We're working on (an offseason plan), exploring a lot of angles internally trying to come up with priorities so we can hit the ground running when the time is appropriate. But in terms of laying that out publicly, it simply isn't the right time."