Stacks are usually the backbone of the best FanDuel lineups, especially in tournaments. Brandon Gdula's piece examining hit rates and correlation for stacks is a must-read article whether you're already familiar with stacking or new to the concept.

This piece will lay out my favorite weekly stacks. So, read on to see the stacks I'm firing up this week.

San Francisco 49ers

Brock Purdy ($6,900) and George Kittle ($7,600)
Bring-back Option: Greg Dortch ($5,400)

Purdy was the headliner for my value plays piece this week. The case for using him remains the same, and if you're saving salary by using him, spending some of the savings on his superstar tight end as a stacking partner makes sense.

Kittle is a monster. Sometimes he takes a backseat to other weapons on the San Francisco 49ers, but Kittle is efficient and on fire. According to Pro Football Focus (PFF), Kittle is tied for fifth in yards per route run (1.76 Y/RR) among the 31 tight ends targeted at least 40 times this season. He is also first in Reception Net Expected Points (NEP) per Target in the same sample of tight ends.

On top of that, Kittle has scored five touchdowns during his three-game streak of reaching paydirt and has at least four receptions in each of his last four games. He also surpassed 90 receiving yards twice in the previous three weeks. Kittle has clearly been on the same page as Purdy.

Finally, Kittle eviscerated the Arizona Cardinals for 4 receptions, 84 receiving yards, and 2 touchdowns in Week 11. Kittle's ceiling is sky-high, making him an attractive choice in tournaments.

San Francisco 49ers-Arizona Cardinals

Christian McCaffrey ($10,000) and Greg Dortch ($5,400)

The 49ers exercised caution with McCaffrey during the week, but he's playing against the Cardinals.

The do-it-all back is in an eruption spot this week. Running backs have hammered the Cardinals. According to The 33rd Team and data from Sports Info Solutions, Arizona has allowed the second-most FanDuel points per game to running backs since Week 11.

Thankfully, McCaffrey is built to take advantage of the cushy matchup. He's scored a touchdown in each of his last five games and had more than 130 scrimmage yards in four of those contests. CMC has taken to San Francisco's offense seamlessly and has dominated. CMC's usage, excellence, and mouthwatering matchup are reflected in his projection this week. numberFire algorithm projects him as the RB1, and CMC is tied for the highest value score -- the measure of points per $1,000 of salary -- at the position.

Dortch is an attractive bring-back option for the first highlighted stack or for CMC. David Blough will start for the Cardinals again this week, and he fed Dortch 10 targets on 40 passes (25 percent target share) in Week 17. Sadly, Dortch had just four receptions for 15 scoreless yards. The volume was excellent, though, and Dortch has a good matchup this week.

Per The 33rd Team, slot wide receivers have tied for the 10th-most FanDuel points per game against the 49ers since Week 11. Meanwhile, per PFF, Dortch played 78 percent of his passing snaps aligned in the slot last week and has played 83.1 percent of his snaps in the slot this season. Dortch isn't the most exciting or highest-ceiling pick, yet he's a value and is tied for the 11th-best value score among wide receivers on FanDuel's main slate.

Seattle Seahawks-Los Angeles Rams

D.K. Metcalf ($7,200) and Cam Akers ($7,300)

Gamers need to have a short memory for Metcalf. Yes, he had a horrendous game last week, catching only one pass for three receiving yards. Still, Metcalf averaged 9.5 targets, 6.9 receptions, 73.4 receiving yards, and 97.5 air yards per game in eight games before his dud in Week 17. He also scored four receiving touchdowns during that eight-game stretch.

The matchup is nifty, too, for the well-built wideout. Metcalf torched the Los Angeles Rams for 8 receptions, 127 receiving yards, and 1 touchdown on 8 targets in Week 13. According to Football Outsiders, No. 1 wide receivers have averaged the fourth-most receiving yards per game (80.3) against the Rams. LA is tied for the eighth-most FanDuel points per game yielded to perimeter wide receivers since Week 11.

As a result, the outlook is outstanding for Metcalf this week. DK is projected as the WR9 and has the seventh-highest value score at the position on Sunday's main slate, per our model.

Akers is a high-upside game-stacking option opposite Metcalf. Akers' early-season struggles and inefficient play from early this year (and late last year) are a distant memory. The third-year pro has rushed for more than 100 yards in back-to-back games and had 100 scrimmage yards in Week 15, as well. He's scored six touchdowns in his past five games.

Akers can punctuate this year emphatically against a soft run defense. According to our team power rankings, the Seattle Seahawks have the sixth-worst rush D. Since Week 11, running backs have averaged the most FanDuel points per game against the Seahawks.

The most significant risk for Akers is the game script turning negative. The Seahawks are 6.0-point favorites. However, Akers can pile up yards against Seattle's soft run defense as long as the Rams keep the game within reach. While Akers isn't without risk, the upside is tantalizing, and his projection is sweet. He's forecasted as the RB7 for Sunday.

Pittsburgh Steelers

Najee Harris ($7,200) and Pittsburgh D/ST ($3.900)

Despite a challenging matchup last week, Harris had 123 scrimmage yards, 2 receptions, and 1 touchdown. The second-year running back had more than 85 scrimmage yards in each of his previous three games and has scored a touchdown in five of his past seven. Harris can feast in a tasty matchup this week.

The Cleveland Browns have the eighth-worst run defense by our metrics. They've also allowed a blistering 4.9 yards per carry and an eye-popping 144.7 scrimmage yards per game to running backs since Week 11. Harris should find ample running room to pile up yardage in this spot.

The game script should be good, too. The Pittsburgh Steelers are 2.5-point favorites. In Pittsburgh's previous seven games, they've attempted 81 passes and 102 rushes by non-quarterbacks when tied or leading. Harris should tote the rock a ton if the Steelers handle their business. He's projected as the RB5 and for the fourth-highest value score at the position.

Finally, the Steelers' defense would also benefit from a positive game script. You can check out my value plays article from earlier this week for more info on why I'm into Pittsburgh's D.

Joshua Shepardson is not a FanDuel employee. In addition to providing DFS gameplay advice, Joshua Shepardson also participates in DFS contests on FanDuel using his personal account, username bchad50. While the strategies and player selections recommended in his articles are his/her personal views, he/she may deploy different strategies and player selections when entering contests with his/her personal account. The views expressed in his/her articles are the author's alone and do not necessarily reflect the views of FanDuel.