Mike Tanier

Let’s say you want to draft a rookie who will make an immediate impact.

Maybe you are last year’s Falcons, who felt they were one playmaker away from the Super Bowl and traded up to select wide receiver Julio Jones. Or last year’s 49ers, who wanted to make a good defense great by adding Aldon Smith to the pass rush. Or you are this year’s Dolphins, who could leave a box of season tickets lying on the street, come back in an hour, and find that none were taken: You need a rookie that will generate excitement.

There are great prospects at every position. But which position will give you immediate results? Rookie running backs often have 1,000-yard seasons. Or do they? Jones had a great year for the Falcons, but how often does that happen? Smith recorded 14 sacks, but can a team expect that from Courtney Upshaw or some other pass rusher?

Let’s look at the past 10 drafts on a position-by-position basis. We will focus on the first round, because when you are looking for immediate help, you don’t wait until later rounds to find it. We will also define an “impact rookie” as precisely as possible to eliminate judgment calls. At what positions do rookies produce the most immediate results?

The answers buck conventional wisdom. Let’s start at the top.

Quarterback
Impact rookies: Start at least 10 games and produce a quarterback rating over 75.0.

Impact rate: 16%
As you might expect, rookie quarterbacks rarely have outstanding seasons. Only Cam Newton, Sam Bradford, Matt Ryan, Joe Flacco and Ben Roethlisberger met our not-too-stringent standards among first-round picks. Lots of rookies fell below the 75.0 rating threshold, including Vince Young, Mark Sanchez and a few others who garnered a lot of attention in their first seasons. Remember, we are looking for “impact” players, not guys who can hold down the job and get by because they make a few plays.

The low impact rate is sobering news for those who hold up Cam Newton as an example of what Robert Griffin III or some other quarterback can do right away. The reason the four players above are mentioned so often is that they are the only good examples from the past decade. Drafting a quarterback is not a quick fix.

Running back
Impact rookies: Gain at least 1,000 yards from scrimmage.

Impact rate: 39%
Surprised? When we think of rookie running backs, we think of Adrian Peterson–types: Point them at the hole, give them the ball, and watch them thunder for 1,300 yards and 12 touchdowns. But most of our impact first-rounders are more like Reggie Bush, Jahvid Best or Knowshon Moreno, barely qualifying after their rushing and receiving yards are mixed together.

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A 39 percent impact ate is still pretty strong, but our list is filled with busts such as Chris Perry and Laurence Maroney, as well as great backs who needed a year or two to get going such as Rashard Mendenhall or Steven Jackson. Even the  “impact” list included players who faded quickly: Moreno, Kevin Jones and William Green.

The message is clear: The first round of the draft is not teeming with 1,000-yard rushers, though the probability of a quick upgrade is higher here than at many other positions.

Wide receiver
Impact rookies: Gain at least 800 receiving yards and score a minimum of four touchdowns.

Impact rate: 22%
Lower the threshold to 700 receiving yards, and the impact rate is much higher. Receivers such as Larry Fitzgerald, Calvin Johnson and Jeremy Maclin all gained between 700-800 yards as rookies. But we are looking for major upgrades here, not guys who come in and show flashes. Eight hundred yards works out to just 50 yards per game. The only rookie first-rounders from the past decade to reach that total were Julio Jones, A.J. Green, Dwayne Bowe, Roy Williams, Michael Clayton, Lee Evans and Andre Johnson.

Just as Newton set a misleading standard for quarterbacks, Jones and Green might set the bar too high for wide receivers. If Fitzgerald and Megatron could only catch 48-58 passes as rookies, it is not fair to pencil 75 in for Justin Blackmon or Michael Floyd. Production like that is rare.