While the Minnesota Twins are getting a key arm back in their rotation with Joe Ryan, his return alone won't be enough to save the team's fading postseason hopes. 

Ryan was placed on the 15-day injury list on Aug. 7, retroactive to Aug. 5, because of a left glute strain. Ryan will start for the Twins against the Detroit Tigers on Monday. 

The Twins currently sit 4.5 games back of a final AL wild-card spot following a 10-1 loss to the Chicago White Sox and are 4-6 in their last 10 games. They were once in sole possession of a final AL wild-card spot following a sweep of the Atlanta Braves in late August. 

They currently face a steep uphill battle in the AL wild-card race with four other teams also pushing to clinch a playoff berth. The Twins also lost slugger Byron Buxton to a hip injury, depleting them of star power. 

The team's performance collapsed in August following a 10-17 record that led to its slide in the wild-card race. Now, with less than a month remaining in the regular season, the Twins' chances of making the postseason have shrunk. Relying on Ryan alone won't change that.

Why Joe Ryan's return won't help fix a rotation that's already taxed

Considering that Ryan has been on the injured list since early August with a strained left glute, he won't be able to carry a heavy workload. While he made a significant stride forward in his minor league rehab start for Triple-A St. Paul on Sept. 1, pitching three strong innings and striking out four, he only threw 42 pitches. 

This means that he will be limited to pitching about three to four innings, not being able to provide durability and save a bullpen that's struggled with an ERA ranking near the bottom of the league at 4.85. 

Before the All-Star break, he put up strong numbers, going 6-5 with a 2.85 ERA and 128 strikeouts across 110 1/3 innings. But prior to landing on the IL, Ryan underwent a post-All-Star break slump where he recorded an inflated 9.39 ERA with 25 hits given up and 17 runs across 15.1 innings and three starts. 

But Ryan has also gone through frustrating stretches in his career, showing a decline in his performance in the second half of seasons that's been triggered by fatigue and injuries. 

He carries a career 3.17 ERA in the first half of seasons compared to a much higher 4.96 ERA in the second half. In addition, Ryan will be returning to a taxed starting rotation that lost Pablo Lopez to season-ending Tommy John surgery, as well as Mick Abel being shut down for the season. 

Beyond Taj Bradley's solid performance, Bailey Ober has struggled, and the Twins have been forced to rely more heavily on rookies like Zebby Matthews and Connor Prielipp. All in all, one pitcher returning on a limited pitch count won't be enough to save a rotation that's become the team's weakest link.