*Rushing Yards Per Attempt Allowed - very straightforward, the average amount of yards allowed per run play.
*Negative Pass Play Percentage - the percentage of passing downs that end with the defense getting a sack or an interception.
*Third Down Percentage - another simple one, the conversion rate given up on the 'money down'.
Last season, the Eagles rated 21st in the league, per the metric's mean. They were an impressive fourth in RYPAA (3.77), but that's where the quality ended. Philadelphia ranked 26th in NPP% (7.92%) and 24th in third down percentage (40.3% converted).
Last night at the Linc, the Eagles' starting defense (who played the first half) strung together a more than admirable performance, striking down the Steelers offense, and shutting them out completely. Efforts from the likes of Mychal Kendricks, Nolan Carroll, and Fletcher Cox, among many others, worked in sync to disrupt a Steelers team that some experts believe will have a bounce-back year in a wide-open AFC North.
Let's look at the numbers of the first-half D.
RUSHING YARDS PER ATTEMPT ALLOWED: 4.30
Slightly up on their 2013 average, the Eagles would have ranked 22nd in the league last year with this Thursday number. Philadelphia allowed 43 yards on 10 carries in the first half, but helpfully, none went for more than seven yards.
NEGATIVE PASS PLAY PERCENTAGE: 11.11%
Roethlisberger dropped back 18 times in the first half, suffering two bad plays: Carroll's interception after Kendricks flushed Big Ben from the pocket, and a Brandon Graham sack to end the half.
If the Eagles defense in 2013 averaged a Negative Pass Play once every nine snaps, they would have maintained the fifth best average in the league, behind only Buffalo, Seattle, Carolina, and St. Louis.
THIRD DOWN PERCENTAGE: 42.85%
The Steelers converted three of seven third downs in the first half, which is a far cry from the Eagles allowing 10 of 15 Patriot thirds to convert a week ago. The three of seven is still up on the already-shaky 2013 average, however.
In fact, the Eagles would have dropped to 28th in the league on third down, ahead of Oakland, Dallas, Minnesota, Cleveland, and rock-bottom Atlanta.
Overall, you can't fault the Eagles defense too much: they brought better pressure, allowed no points, and made some big plays, both with turnovers and key third down stops.
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