Final MLB Trade Deadline Fantasy Baseball Breakdowns: Mize, Griffin and More

As promised, let's go over the final batch of MLB trade deadline deals, breaking things down from a fantasy baseball perspective.

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Padres Land Mize

San Diego acquired Casey Mize and Gage Workman from Detroit right near the trade deadline buzzer. The Tigers got Kash Mayfield and Jackson Wolf in return.

Mize has been great when healthy this season. Over 16 starts, he's 4-6, but with a 2.70 earned run average. He has 85 strikeouts over 86 2/3 innings.

San Diego is deciding to go for it a bit, and Mize will help in that cause. His fantasy outlook isn't altered too much from the trade. He will remain a good option in all fantasy leagues, especially if he stays healthy the rest of the season.

Workman has appeared in just 16 games so far this season, sporting a .158 average and on-base percentage. He can play a few positions, so he's organizational depth, and not a very big fantasy asset unless he's playing in the big leagues daily and producing.

Mayfield is the new No. 6 prospect for Detroit, which sold at the trade deadline. Mayfield is 21 years old, has a 2028 ETA and has been working in High-A. The trade helps his chances of making the big leagues sooner, but a late 2027 debut seems most likely right now.

Wolf is 27 years old and has spent the year in Triple-A. He has a 7.56 ERA there, and last played in the big leagues in 2023, so I don't see much fantasy value with Wolf, even if he's called up to the big leagues.

Griffin Acquired by Guardians; Lowe also Added

Another late deal was the Guardians getting Foster Griffin from the Nationals - Cleveland sent Washington Josh Hartle, Will Dion, Kendeglys Virguez and Nick Mitchell in return.

In another deal, Cleveland got Nathaniel Lowe from the Reds, sending Alejandro Rivera in return.

After spending 2023-25 in Japan, Griffin pitched well across 22 starts for the Nats. He was 12-3 with a 3.06 ERA over 129 1/3 innings - he struck out 116 along the way.

Griffin adds a quality starting pitcher to the Guardians' rotation, and that boosts the team's chances of winning the AL Central and maybe making a postseason run. Griffin's fantasy outlook goes up a bit, so keep expecting good things out of him the rest of the season.

Lowe has a .266 average and .341 OBP over 83 games and 276 plate appearances this season. He adds a first base/designated hitter option for Cleveland. Lowe's fantasy outlook improves just a bit, and he could be worth some deep-league adds/utilization the rest of the season.

Hartle is the Nationals' new No. 29 prospect. The 23-year-old is pitching in Double-A and has a 2027 ETA. He's got good numbers over the past two years, so we'll see if he can keep rising as a prospect as he nears a big league call up.

Dion made his debut earlier this season, and has pitched 19 2/3 innings over 12 appearances - he has a 4.58 ERA. He doesn't have much fantasy value, even after the trade, and his dynasty value is low too as a 26-year old.

Virguez is 22 years old and was pitching in Double-A before the trade. He has a 4.13 ERA this season, and 5.70 ERA overall, which explains why he's not a ranked prospect. We'll see if the Nats can turn him into anything.

Mitchell is 22 years old and was playing in AA before the deal was made. He has a .240 average and .358 OBP this season, along with a .262 average and .370 OBP over three career minor league seasons. Again, he's not a huge prospect, but a change of scenery could help him out, so keep tabs on him.

Rivera is just 19 years old and has made it to Single-A. The pitcher has a 3.40 ERA so far across two levels of play this year, and a 2.21 ERA overall, so we'll see if he can keep rising as a pitching prospect.

Diamondbacks Trade for Nootbaar

Arizona landed Lars Nootbaar from the Cardinals near the deadline. Daniel Eagen, Sandro Santana and a player to be named later were the return.

Nootbaar has a .234 average and .333 OBP across 48 games and 183 plate appearances this season. He gives the D-Backs some outfield depth, but he's not likely to be more than a deep-league fantasy asset this year.

Eagen is St. Louis' new No. 17 prospect. The 23-year-old has been pitching in Double-A and has a 2027 ERA. The trade may move his ETA up a bit, but it's still likely to come next season.

Santana is the No. 22 prospect for the Cards. The 21-year-old pitcher was working in AA as well, and also has a 2027 ETA. Santana has really good numbers over the past two seasons, so he's one to keep tabs on, especially if he keeps pitching well as he rises the minor league ranks.

Twins Add Hoffman

Minnesota got Jeff Hoffman from the Blue Jays. The Twins sent Dasan Hill, John Klein, Dameury Pena and international bonus pool money in return.

Hoffman appeared in 51 games for Toronto this season. He was 6-7 with five saves, four blown saves and 12 holds. Hoffman had 75 strikeouts over 48 innings, while posting a 3.94 ERA.

He's got a chance to close games in Minnesota, so he's one to add in more fantasy leagues today, at least in deeper leagues. Keep tabs on him in case he takes off with the Twins.

Hill is the new No. 6 prospect for the Blue Jays after the trade. The 20-year-old pitcher has a 2028 ETA and has been pitching in High-A. He's struggled a bit this season, but is still highly regarded, so he's one to stash in dynasty leagues and keep tabs on down the line.

Klein is ranked 25th for Toronto. He made his MLB debut earlier this year, and has 4 1/3 MLB innings under his belt. The primary starter in the minor leagues had a 4.54 ERA down there, so his fantasy outlook isn't anything spectacular, but he could have a little fantasy value if he's working in the big leagues.

Pena is only 20 years old and has made it to High-A. He can play several spots, which could help his cause way down the line, but right now, he's not a highly-regarded prospect.

Giants, Red Sox Swap Players

Boston got Erik Miller and Carlos Gutierrez in a deal with San Fran. The Giants landed Marcelo Mayer in return.

Miller has a 2.76 ERA over 38 appearances and 32 2/3 innings this season. He has 45 strikeouts along the way. He gives the Red Sox' bullpen another arm, but his fantasy value will be capped at deep leagues, as he won't be an option for saves.

Gutierrez is the No. 14 prospect for Boston after the trade. The 21-year-old outfielder has a 2028 ETA and has been playing in High-A. He has really good minor league numbers, so he's a player to possibly stash in dynasty leagues, especially deeper ones.

Mayer never panned out to be the high-level prospect he was touted to be in Boston. Across 114 MLB games so far, Mayer has a .223 average and .278 OBP.

Maybe a change of scenery will do him well. He's on the 10-day IL right now, but could be in the big leagues when activated. Keep tabs on him in case he takes off with the Giants.

Brewers Get Senzatela from Rockies

Milwaukee made a second deadline day deal, getting Antonio Senzatela from the Rockies in exchange for Mark Manfredi and Juan Martinez.

Senzatela has fared well in his first season as a reliever. Across 34 appearances and 52 1/3 innings, he's got a 9-2 record, 3.61 ERA and 45 strikeouts.

He'll be a late-inning relief option for Milwaukee, but not likely to earn saves, which caps his fantasy value. Senzatela could still be worth some deep-league utilization the rest of the season though.

Martinez is the No. 26 prospect for Colorado after the deal. The 19-year-old infielder has a 2029 ETA and has been in Single-A. He's hit really well the past two years, so we'll see if he can keep rising in Colorado.

Manfredi is a 26-year-old pitcher who has pitched in AA and AAA this season. He has a 3.35 ERA, so he's an option for a big league call up. Pitching in Colorado isn't a great thing, but maybe Manfredi could have a little fantasy value at least.