Our daily fantasy helper is available every day to analyze FanDuel's main slate and help give you a starting point when you're building lineups.

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Let's check out the top options on today's main slate.

Pitchers

Luis Castillo ($11,000)

Seattle's hard-throwing right-hander is today's most expensive option among Sunday's 26 pitchers in his second start this season versus a Kansas City Royals' offense with a 25.1% K-rate and .319 weighted on-base average (wOBA) in their last 2229 plate appearances.

Through his second season with the Mariners, Castillo has continued to record strong production with Seattle, accounting for a 3.64 expected Fielding Independent Pitching rating (xFIP), a 27.6% strikeout rate, and a 15.0% swinging strike percentage.

While some may hesitate at Castillo's recent increase to his highest salary point this season, the Mariners' ace still ranks third in value with a 3.69 rating and first overall with a 40.0 FanDuel point projection with 6.12 strikeouts.

Aaron Nola ($9,800)

After a recent drop to his second lowest salary point this month, Philadelphia's veteran has an optimal spot to record a quality start versus a St. Louis Cardinals' unit with a .310 wOBA and a 21.5% K-rate.

In his last four starts, Nola has followed his strong performance in July (3.14 xFIP) with another solid stretch during August, accounting for a 3.58 XFIP, 27.7% K-rate, and six or more strikeouts in 75% of his recent appearances.

With an above average 11.1% swinging strike percentage during this time period and outstanding splits against right-handed bats this season (3.53 xFIP, 25.2% K-rate), Nola has the ideal matchup to reach his 34.0 fantasy projection against six righty Cardinal hitters with K-rates between 18.2% and 29.9%.

Jack Flaherty ($8,600)

At his lowest salary during his brief tenure with the Orioles, Flaherty has the right spot to provide sneaky value against a Colorado Rockies' lineup with a .296 wOBA and a 27.9% K-rate versus right-handers this season.

While the 27-year old struggled in his last outing, Baltimore's starter has displayed strikeout production close to his careers norms (26.9% K-rate. 12.6% swing strike rate) with his new team, producing a 13.5% swinging strike percentage and a 28.8% K-rate in three starts during August.

Stacks

Toronto Blue Jays

After breaking out of their recent slump with eight runs on Saturday, the Blue Jays rank as today's top offense with a 5.28 expected run total against Noah Syndergaard.

During his time with Cleveland, "Thor" has really struggled in five starts, recording a 5.92 xFIP and an ugly 12.5% K-rate while his seasonal metrics display a similar profile with career-worst expected metrics including a 5.11 xFIP and a 4.99 Skilled Interactive Earned Run Average.

Ideal Toronto combinations can utilize their top right-handed bats to attack Syndergaard's unique reverse splits this season (5.40 xFIP, .402 wOBA) with a main focus on Bo Bichette (9.3% barrel rate, .366 expected wOBA), Vladimir Guerrero Jr. (11.5% barrel rate, .385 expected wOBA), George Springer (.332 expected wOBA, 8.5% barrel rate), Davis Schneider (.429 expected wOBA, 20.0% barrel rate), Matt Chapman (.341 expected wOBA, 17.2% barrel rate), and Danny Jansen (10.2% barrel rate).

Philadelphia Phillies

After an impressive 12-run output on Saturday night, the Phillies remain a strong choice for stacking with a 5.17 expected run total against rookie Drew Rom.

While Rom's sample size is extremely limited after making just one MLB start, the Cardinals' left-hander has displayed poor expected metrics (4.70 XFIP in 2023, 4.13 xFIP in 2022) and a troubling lack of command throughout his time in the minors (11.5% in Triple-A during 2023, 10.9% in 2022) despite keeping the ball mostly on the ground (47.7% in 86.0 innings).

Wit his profile in mind, Philadelphia stacks can group their top power hitters who tend to lift the ball in the air including Kyle Schwarber (25.5 fly-ball percentage, 15.1% barrel rate), Trea Turner (36.% fly-ball percentage, 7.1% barrel rate), Nick Castellanos (28.0% fly-ball percentage, 10.7% barrel rate),Bryce Harper (24.1% fly-ball percentage, 14.0% barrel rate) and J.T. Realmuto (32.5% fly-ball percentage, 11.3% barrel rate)

Baltimore Orioles

In a matchup versus Ty Blach, the Orioles contain an underrated 4.99 run total against a regressing left-hander with expected marks (5.19 xFIP) almost one run higher than his current 4.38 Earned Run Average.

While Blach has done a good job keeping the ball on the ground (41.3% rate), optimal Baltimore stacks can feature their top fly-ball hitters to counter his top method of producing outs, including Ryan Mountcastle (33.3% fly-ball percentage, 13.6% barrel rate), Anthony Santander (32.8% fly-ball percentage, 11.0% barrel rate), Austin Hays (28.4% fly-ball percentage, 9.4% barrel rate), and James McCann (32.2% fly-ball percentage, 7.5% barrel rate)

Seattle Mariners

Despite averaging a red hot 6.2 run average during August, the Mariners could be a forgotten stack on Sunday with a 4.93 expected run total against Kansas City's inexperienced right-hander Alec Marsh.

In his first stint in the Majors, Marsh has profiled as a below-average pitcher at the big league level, recording a 5.40 xFIP and a worrisome 12.5% walk percentage in six starts while allowing an eye-popping amount of hard contact including a 10.7% opposing barrel rate and a 21.1% home run to fly-ball ratio.

With his main weaknesses in focus, any of Seattle's top power bats should be a priority on Sunday including Julio Rodriguez (10.9% barrel rate, .460 expected slugging percentage), Teoscar Hernandez (14.4% barrel rate, .483 expected slugging percentage), Eugenio Suarez (13.8% barrel rate, .443 expected slugging percentage), and Cal Raleigh (.470 expected slugging percentage, 13.6% barrel rate).

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The above author is a FanDuel employee and is not eligible to compete in public daily fantasy contests or place sports betting wagers on FanDuel. The advice provided by the author does not necessarily represent the views of FanDuel. Taking the author's advice will not guarantee a successful outcome. You should use your own judgment when participating in daily fantasy contests or placing sports wagers.