We’re approaching mid-May — essentially a quarter of the way into the 2019 MLB season — and free-agent pitcher Dallas Keuchel, the seventh-best lefty in baseball over the past five full seasons according to wins above replacement,1Averaging together the versions from Baseball-Reference.com and FanGraphs. is still without a team.“If you would’ve asked me on the first day of free agency, I would have said no way I’d be here on May 6,” Keuchel told Tim Brown of Yahoo Sports this week. “This was not the plan at all. I would love to be out there playing ball and helping a team win. Because, to my career at this point, I’ve done more winning than I have losing and at a much higher clip. So what team wouldn’t want me to be out there?”So what’s keeping Keuchel on the sidelines? He is reportedly holding out for what he calls his “fair market value,” even turning down offers recommended to him by his agent, Scott Boras. And Keuchel’s current offers may be affected by the fact that any team signing him would have to send a compensatory draft pick to his former club, the Houston Astros. (This obstacle will be lifted after next month’s draft.)But pushing in the opposite direction is the fact that there are indeed teams that should want Keuchel and are hurting themselves by waiting to pull the trigger. Although we think of the most important games in a pennant chase happening down the season’s final stretch, these games in May count just the same in the standings — and even now, there are already teams running into crises in the back ends of their rotations.To see which teams could use Keuchel’s services the most, we took our pitcher ratings and compared each rotation’s current strength2Averaging the ratings for a team’s five highest-rated pitchers, among those who started at least three games this season and at least one game in the past 10 days. to what it would be with Keuchel replacing the team’s fifth-ranked starter. Although the teams Keuchel would help most are generally bad teams, the ideal mix would be a team with a good Elo rating but a thin rotation in need of a solid starter. Looking at the current state of things, the best fits are the St. Louis Cardinals (where Keuchel’s rating is a vast improvement over that of current No. 5-ranked starter Dakota Hudson), the Cleveland Indians (Jefry Rodriguez), the Boston Red Sox (Hector Velazquez) and perhaps the Oakland A’s (Aaron Brooks).Of course, the Indians — who are currently missing Mike Clevinger and Corey Kluber (both of whom rate higher than Keuchel) — are proof that just because a team’s rotation is wracked with injuries now doesn’t mean it won’t eventually get stronger. When Cleveland is at full strength, it will have little need for Keuchel because he would actually rate worse than the Tribe’s fifth-ranked starter, Shane Bieber. Ditto the Red Sox, who will get David Price and Nathan Eovaldi back sooner or later, mitigating Keuchel’s impact as a rotation upgrade.But St. Louis remains the team that could use Keuchel most, even if we look at who they might add internally during the season. (The injured Carlos Martinez, who carries a pitcher rating of 51.8 — exactly the same as Keuchel’s — will return soon, but only in a relief capacity.) The Cardinals’ need for Keuchel makes sense considering how little they have gotten out of the back of their rotation so far this season. (Hudson, Adam Wainwright and Michael Wacha have all posted earned run averages at least 9 percent worse than the National League average.) With at least some luxury-tax breathing room and an extremely competitive NL Central race in front of them, the Cardinals might be the team with the most to gain by adding an experienced, solid starter like Keuchel.At age 31 this season, Keuchel is probably not the pitcher he was just a few years ago. Indeed, his Elo pitcher rating dropped from a very strong 59.2 in the middle of the 2017 season to a more middling 51.8 — only 55th-best in baseball — by the end of last season. Keuchel himself knows where he’s at — but he also knows he can still help a team in 2019.“Am I the best at this point in time? No,” he told Yahoo. “But am I more than or better than some of the offers I’ve been given? Absolutely.”Check out our latest MLB predictions.