All season, this space has kept track of four specific statistical trends, chosen because they are simple enough to understand yet more telling than Notre Dame’s yardage totals or time of possession extremes. Turnover margin keeps an eye on momentum-swinging errors. Yards per pass attempt indicates any penchant for big plays. Rush attempts per game tells of a confidence relying on the ground game. Third down conversion percentage speaks to overall offensive success.
They showed last season’s defense gave up passing yards and third down conversions at rates beyond overcoming. They emphasized the Irish running game and dependence on turnovers at the 2017 midseason mark. They underscored Notre Dame’s defensive stinginess at this season’s peak, the October wins over USC and North Carolina State.
The fall from that peak was quick. Due to a convenience of the calendar, the season’s storylines break cleanly into September and October versus the four games in November. The only messiness comes from removing some Navy exceptions — the Midshipmen’s 72 rush attempts spike that average, for example.
All laid out below, one of these four predicators stands out.
The turnover drop-off on defense and influx on offense cannot be emphasized enough. More precisely, the rise in Irish giveaways marred November more than anything else.
In the season’s first two months and eight games, Notre Dame turned over the ball only seven times. That rate more than doubled to eight times in November’s four games. Those eight feckless possessions may as well have been touchdowns forfeited.
When not turning over the ball, the Irish offense reached the end zone on 35.81 percent of its possessions this year. That number ticks further upward when accounting for indifferent possessions at the end of halves, but for this exercise, let’s use 35.81 percent.
Without turnovers, such a rate would have delivered Notre Dame another touchdown this weekend at Stanford. Also without those turnovers, the Cardinal would not have scored twice in short fields. Suddenly this thought exercise produces a 27-24 score in favor of the Irish.
The same logic creates a hypothetical 18-17 result in Miami on Nov. 11, again tilting toward Notre Dame.
Aside from that glaring and crippling factor, the Irish offense was viable in November. Junior quarterback Brandon Wimbush averaged more yards per pass attempt, a sign of finding consistency in producing big plays. The drop in rush attempts per game ties to playing catch up at Miami, only running 31 times.
It may seem overly simplistic, but the flip in turnover margin is the statistic that jumps off the page. A truly elite defense may have counteracted that trend or perhaps an undeniably lethal offense could have scored touchdowns more often than 35.81 percent of the time.
However, for a good team showing glimpses of being very good in mid-to-late October, the simultaneous sloppiness on offense and lack of fortuitous bounces on defense were far too much to overcome.
RELATED READING: Friday at 4: Four key statistical tidbits (Sept. 1)
A statistical look at Notre Dame’s offense through six games compared to the past (Oct. 11)
Notre Dame’s defense has limited scoring, but what keys have led to that? (Oct. 12)
Friday at 4: A statistical look at how Notre Dame routed two top-15 teams in consecutive weeks (Nov. 3)
Turnover margin
First eight games: +11
Last four games: -6
12-game season: +5
Considering the Irish did not turn the ball over against Wake Forest but did force a turnover, the November data becomes even more foreboding when narrowed to the last three games and a -7 differential, including seven turnovers in the two losses alone.
Yards per pass attempt
| Offense | Defense (allowed) |
| First eight games: 5.96 yards | First eight games: 6.00 yards allowed |
| Last four games: 7.43 yards | Last four games: 8.56 yards allowed |
| Nov. excluding Navy: 8.93 yards allowed | |
| 12-game season: 6.51 yards | 12-game season: 6.22 yards allowed |
| Season excluding Navy: 6.24 yards allowed |
Navy attempted eight passes for 41 yards. Removing such from the defensive data allows for a bit more accurate overall picture.
Rush attempts per game
| Offense | Opponents |
| First eight games: 44.63 | First eight games: 31.63 |
| Last four games: | Last four games: 47.25 |
| Nov. excluding Navy: 38.00 | Nov. excluding Navy: 39.00 |
| 12-game season: 41.75 | 12-game season: 36.83 |
| Season excluding Navy: 42.82 | Season excluding Navy: 33.64 |
The Midshipmen rushed 72 times. That skews one half of this data if not removed. Notre Dame had seven genuine offensive possessions, rushing only 30 times against Navy, skewing the other half. For context’s sake: That is even fewer rush attempts than the Irish attempted when trailing so resoundingly against Miami.
Third down conversion percentage
| Offense | Defense (allowed) |
| First eight games: 43.33 percent | First eight games: 34.09 percent |
| Last four games: 44.07 percent | Last four games: 32.14 percent |
| Nov. excluding Navy: 26.32 percent | |
| 12-game season: 43.58 percent | 12-game season: 33.51 percent |
| Season excluding Navy: 32.35 percent |
Navy converted 8-of-18 third downs, skewing the data both in attempts and in success rate. Removing that from November, one sees defensive coordinator Mike Elko’s unit may have held its own down the homestretch. Rather, it gave up big plays more often, as exhibited by the yards per pass attempt. While Notre Dame halted its November opponents more frequently on third downs, it also gave up touchdowns on 33.33 percent of possessions, up noticeably from only 16.38 percent in September and October.
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