There are a few rules to live by in fantasy football, such as, never take a kicker before the final round. Here’s another important rule: Don’t assume that whatever happened last year will happen again this year.

One of the challenges in fantasy football is that the real-life sport on which it’s based equates to a minefield of small sample sizes. Even an entire season consists of just 16 games — less than a fifth of what NBA and NHL players are given to prove their worth, never mind baseball’s marathon slog — and, of course, injuries limit many players to fewer than that, not to mention the annual Week 17 second-string wackiness.

With that in mind, here are a few players whose 2017 performances are unlikely to be replicated, particularly in the often fickle area of touchdowns. In these four cases, former studs may appear somewhat less studly than they did in 2017. On Friday, we’ll look at four players who performed below their averages in 2017 that may have better seasons ahead in 2018.

Deshaun Watson, QB, Texans

Watson streaked like a comet across the NFL firmament, racking up in just five games (once he got his feet wet in his first two appearances) a whopping 1,472 passing yards and 18 TDs, with an extra 186 rushing yards and another score. If he could do that as a rookie, before tearing a knee ligament, imagine what he could do in a full season, right?

Well, maybe, but let’s remember that if an NFL season represents a small sample size, five games is darn near microscopic. More importantly, Watson posted a passing TD rate of 9.3 percent, which not only led the NFL by a mile (Carson Wentz was next at 7.5, and Aaron Rodgers followed at 6.7), but tied for the 12th-highest mark in NFL history among QBs with at least 200 attempts.

In fact, since 1976, only once has any other QB — Peyton Manning (9.9), in 2004 — notched a TD percentage of 9.0 or greater on at least 200 attempts. So that sucker is coming down for Watson, and the comet may just crash to Earth.

OJ Howard, TE, Buccaneers

Did a heck of a lot with relatively little as a rookie, turning just 39 targets into 26 catches for 432 yards and six TDs. Howard was able to accomplish that by posting by far the highest yards per target of any TE with a minimum of 30 targets. His mark of 11.08 that was well ahead of second-place Rob Gronkowski’s 10.32, and Howard also had the most yards per reception (16.62).

It says here that Howard won’t be repeating those feats, which were aided by two long TDs on which he was as wide open as you’ll ever see an NFL player. Think opposing defensive coordinators might be looking for this play now?

Alvin Kamara, RB, Saints

There’s really not a ton to say here, except that averaging 6.1 yards per carry is patently unsustainable, as is scoring 13 TDs on 201 touches for a rate of 6.4 percent, and averaging 10.2 yards per reception might be hard to keep up, as well. Per Scott Barrett of Pro Football Focus, out of 2,173 times since the 1970 AFL-NFL merger that an RB has had at least 100 carries in a season, Kamara’s 2017 campaign ranked first in fantasy points per touch and second in yards per touch.

Of course, Kamara almost certainly will get more touches this season, which could offset a loss in efficiency and help him return his current first-round value. Just please don’t expect what we saw last year.

JuJu Smith-Schuster, WR, Steelers

As with Howard, Smith-Schuster didn’t let his rookie status prevent him from leading everyone at his position in yards per target (min. 30 targets). His mark of 11.61 was notably better than even that of big-play machine Tyreek Hill (11.27), and it was the ninth-best figure for any WR over the past 10 seasons.

As with Kamara, Smith-Schuster should see the ball more this season, but with another talented rookie WR on hand in James Washington and TE Vance McDonald set for a bigger role, it may not be a lot more. There’s still reason to be excited, but reasonable expectations of regression tell us to temper it just a tad.

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