MOBILE, Ala. — As Senior Bowl practices unfolded at the University of South Alabama this week, numbers flashed on the giant video screen at Hancock Whitney Stadium: speed leaders, by position, and notable speed statistics. A defensive lineman, Marshawn Kneeland of Western Michigan, reached nearly 20 miles per hour while chasing a run play down the sideline. Kentucky defensive back Andru Phillips hit 20.7 miles per hour while breaking up a pass in one-on-one drills.
Zebra Sports, the NFL’s player and ball tracking technology partner that facilitates enterprises such as Next Gen Stats, also collects tracking data from spring all-star events such as the Senior Bowl and East-West Shrine Bowl.
At the Senior Bowl, data is collected via roughly 20 sensors set up around the field, which communicate with small tags players wear underneath their shoulder pads. The tags are about the size of a nickel. Zebra uses radio frequency identification (RFID) technology, which client services supervisor Dominic Russo says is accurate within six inches. GPS tracking data, Russo said, is accurate within 39 inches.
All NFL teams have access to Zebra’s tracking data via the all-star events through the spring. The general public can access a portion of this data, including positional metrics such as maximum speed (measured in miles per hour), acceleration/deceleration and the frequency at which a player records an outlier or “explosive effort,” and distance traveled.
For skill players, acceleration/deceleration translates into a change of direction and/or ways that player creates separation from defenders. NFL teams are able to see how much separation a skill player creates (or prevents, in the case of cornerbacks) on any given route and on average, how quickly they can achieve their top speeds.
“Maybe it isn’t the top speed they want to be looking at,” Russo said, “maybe it’s, ‘How quickly can he get to 10 miles per hour in the first 5 yards of a route?’ If a guy can get there faster, but his top-end speed might not be as high, maybe that’s more important than that top-end speed.”
Teams add Zebra’s tracking data to their ever-evolving evaluations on players through the pre-draft process. Each NFL team has an online system, designed and programmed uniquely to its scouting department, where data and player assessments are input and stored.
It’s important to remember that tracking data is packaged among many other variables that teams use to evaluate players, and that all teams weigh their respective pools of data differently.
For example, the Los Angeles Rams are known for placing far less value on a player’s 40-yard dash time than his movement data from events such as the Senior Bowl or in partnership with some colleges who also use a form of tracking technology, when matched with game film.
The most publicized example is Cooper Kupp, the 2017 third-round draft pick who won the Triple Crown in 2021, after his slow 40 time sunk his draft stock. The Rams weighed tracking data they got from Kupp’s route running at the Senior Bowl, as well as his college tape, much higher than they weighed his straight-line speed (at that time, it was acquired via GPS data). The Rams used a similar process in 2020 to identify starting safety Jordan Fuller in the sixth round (though not with Senior Bowl data) to see how well he got into position and second-round receiver Van Jefferson (who was tracked by Zebra as the fastest player at the Senior Bowl in 2020). Tracking and separation data was again a useful tool in 2023 when evaluating fifth-round receiver Puka Nacua, who last season set all-time rookie receiving yards and catch records, although Nacua didn’t get a full week at the Senior Bowl due to an injury.
Mueller: How an NFL GM approaches the Senior Bowl: What matters and what doesn’t?
Standout Seattle Seahawks cornerback Riq Woolen’s speed topped out at 22.45 miles per hour at the Senior Bowl in 2022 — the fastest ever for the event — before he ran a 4.26-second 40-yard dash at the NFL Scouting Combine a month later. NFL team personnel who didn’t see it live wanted to know more about how Woolen attained that top speed at the Senior Bowl and were able to go back through the tape of the practices to match the data point with film to paint a clearer situational picture in their evaluation.
Even teams that place less weight on specifically a player’s 40 time do still use it as one tool combined with many others throughout the evaluation process, including in conjunction with tracking data.
Above-average straight-line speed without above-average change-of-direction speed is one obvious combination to flag. Would the player only thrive in situational usage? If a player has great tracking data but consistently terrible 40-yard-dash times, the scouting department can dig further into why his straight-line speed is suffering, or even into the testing environment.
The data that matters more (and therefore the questions asked about that data) depends on the team and its overall philosophy as a scouting staff, plus traits that team wants in players for specific roles in its scheme.
One AFC scout, who spoke on the condition of anonymity because he was not authorized to do so publicly, noted that timing-based offenses looking for receivers might especially weigh tracking data points such as acceleration and deceleration, change of direction, the speed at which they reach certain parts of their route and more. That team has to know that a player could reach a point on a field — and be open — at a specific time in the play in correlation to their scheme.
“Each team has its own flavor in how it uses (the data),” Russo said. “Some teams, at the very basic level, speed is obviously a very easy thing to look at. It could be a form of validation (of film), it could be ‘Hey, maybe we give a second look, we didn’t think this guy was that fast on tape but the data is showing otherwise.’
“Another aspect of it is really diving into the raw data and breaking it down more in-depth for individual players and trying to find guys that fit their system, or might be similar to someone that plays in their system that they would like to have on their team.”
According to Russo, one-third of NFL teams also use Zebra’s tracking technology in their practice facilities to record daily movement from workouts. Similar to the all-star events, the depth of information teams are interested in varies.
“(The tags) go in the shoulder pads and the jerseys and they stay there the entire year,” Russo said. “Some teams will embrace the data and really dig into the nitty-gritty, other teams are just using it for speed, which is fine. You want to use it for whatever you think is going to help you.”
(Top photo of Marcus Rosemy-Jacksaint: Vasha Hunt / USA Today)