With a quarter of the 2012-13 NBA season in the books, fantasy leagues are beginning to take shape. Many of the teams that find themselves in first place are at the top their league’s standings due to surprisingly impressive performances from mid-to-late round draft picks.

So often, it is these underrated, undervalued stars that make all the difference in leagues across the land. We all have a pretty good idea of what to expect from the elite, top-tier picks such as LeBron James, Kevin Durant or Chris Paul. However, when GM’s can get first-round production from a seventh-round selection, those teams become very difficult to defeat…

As we glance back at drafts held during October, highlighted below are the best “Draft Day Values” over the first six weeks of the season:

O.J. Mayo – Dallas Mavericks (Average Draft Position in October = 88 // Current Rank in 9-Cat Leagues = 21):
After languishing on the bench in Memphis for a couple of seasons, Mayo hit free agency this summer looking for an opportunity to start. Some (myself included) were skeptical he could thrive as a starting shooting guard, but O.J. has proved any and all doubters wrong by posting some of the most unexpectedly impressive stats in the NBA thus far this season. With Dirk Nowitzki sidelined due to a knee injury, Mayo has emerged as the focal point of the Mavs offense. O.J. is currently one of only eight players in the league averaging over 20 points per contest. Furthermore, Mayo and Carmelo Anthony are the only two players in the NBA averaging at least 2.5 three-pointers, in addition to 20+ points. The primary reason for Mayo’s spike in scoring has been his incredible increase in efficiency. Over his previous two seasons as a member of the Grizzlies, Mayo shot just 40.7 percent from the floor, 36.4 percent from behind the arc, and 76.4 percent from the free-throw line. This year in Dallas, Mayo is posting career-highs across the board, shooting 48.9 percent from the field, 83.3 percent from the line, and a blistering (league-best) 52.5 percent from three-point territory… It’s safe to assume his percentages will creep back towards a more sustainable level, and Mayo’s field goal attempts will obviously decrease a bit when Dirk returns (possibly in January), but its clear O.J. has earned the trust of Rick Carlisle and the Dallas coaching staff, so there’s no reason to suspect Mayo’s numbers will decrease dramatically anytime soon.

Tim Duncan – San Antonio Spurs (ADP = 69 // Current Rank = 5):
Coming into this season, many fantasy players were skeptical of Timmy D as well – but for a far different reason. Although Duncan had continued to put up solid and relatively impressive numbers during the truncated 2011-2012 campaign, how much tread did the former MVP have on his tires? After 16 arduous seasons, was Duncan finally running out of gas? The answer is an emphatic “no.” In fact, the brilliant big man is posting (considering his age) some of the most awe-inspiring stat lines of his entire career. His efficiency on both offense and defense has been phenomenal. Consider this: During the 2000-01 season, when Duncan was 24 years old and finished second in MVP voting, he averaged 20.6 points (49.9 FG% and 61.8 FT%), 11.3 rebounds and 2.2 blocks per-36 minutes. Here are his per-36 minute averages thus far this season: 21.1 points (51.5 FG% and 78.4 FT%), 12.3 rebounds and 3.1 blocks. Those are just jaw-dropping numbers. The rebounds, blocks and FT% would all represent career highs. Despite the fact that he will turn 37 years old later this season, Timmy D is somehow more effective/efficient than he’s ever been… However, looking at the big picture, if you own Duncan, you may want to consider trading him soon. Even if Duncan remains healthy all season, Coach Popovich will limit his playing time late in the season. This will include Coach Pop’s annual tradition of sporadically sitting his stars on occasion, as the Spurs prepare for the playoffs (which has already irked David Stern). Factoring the likely regression to more sustainable numbers, and the definite reduction in playing time late in the season (quite possibly during the fantasy playoffs for those in head-to-head leagues), trading Duncan now may make the most sense long-term.

Stephen Curry – Golden State Warriors (ADP = 41 // Current Rank = 13):
The major question mark surrounding Steph Curry back in October was whether or not the precocious point guard could stay healthy. A preseason ankle injury scared many away, which resulted in Curry slipping in drafts across the land. Those brave souls that shrewdly rolled the dice and scooped up Curry have been reaping immense benefits ever since. Personally, I grabbed Curry in each and every league I could. All things being equal, as long as Curry stays on the floor, he is a truly elite fantasy superstar. And although Curry is universally derided as “injury prone,” he’s actually played in 203 of 253 possible games – that’s over 80 percent. Curry hasn’t missed a game yet this season, and, as a result, he’s been an absolute fantasy force. There are only two players in the NBA currently shooting over 43 percent from the floor, 43 percent from behind the arc and 89 percent from the FT line: Kevin Durant and Steph Curry. Steph is also averaging a career-high 6.5 assists and 2.7 three-pointers.

Anderson Varejao – Cleveland Cavs (ADP = 85 // Current Rank = 12):
Varejao had been a solid and dependable fantasy contributor throughout his first eight NBA seasons. But in his ninth campaign, Varejao is putting up incredible, career-best numbers across the board. Coming into this season, Anderson had averaged fewer than 11 points and two assists per game each year. This season, he’s pouring in over 14 points per contest and dishing out 3.3 dimes each night, as well as shooting a career best 76.5 percent from the free-throw line (he’s never finished a season above 67 percent). However, we all know it’s been the phenomenal rebounding numbers that have vaulted Varejao to the top of the fantasy ranks this season. He’s up over 14 boards a night now, and he has grabbed at least 12 rebounds in 14 of the Cavs’ last 15 games. Zach Randolph, who is second in the league in rebounding, is averaging a full two rebounds less than Varejao.

Jason Kidd – New York Knicks (ADP = 132 // Current Rank = 11):
Much like Tim Duncan, it was assumed by most that Kidd was running on empty and his days as a fantasy contributor had finally come to end. However, Kidd must have discovered the fountain of youth in the Big Apple, because he’s playing at an incredibly high level so far this season. Kidd currently ranks in the top five of the NBA in a multitude of categories this season. He ranks second in the NBA in three-point percentage, shooting 52.8 percent from behind the arc. Kidd ranks second in the NBA in assists/turnover ratio at 4.23. He’s also second in the NBA in steals per turnover and 10th in steals per game. The most impressive aspect of Kidd’s sustained excellence throughout his NBA career has been his continued improvement as a player. Consider this: During his rookie season in Dallas back 1994-95, Kidd shot just 27.2 percent from three-point territory and 69.8 percent from the free-throw line. Well, 18 years later, Kidd is currently shooting 52.8 percent from behind the arc and cashing in 92 percent of his free-throws. As we know, he also chips in his fair share of assists and rebounds.  As long as he stays relatively healthy, Kidd will continue to contribute across the board.

Honorable Mentions: Joakim Noah, Andrei Kirilenko, Kemba Walker, Chandler Parsons, Kevin Martin