There are few things more frustrating in sports than not seizing valuable opportunities when they present themselves. The discouraging consequences of near defeat can have pronounced effects on a team’s performance and morale.

In the last three games, the Yale defense has taken it upon itself to view each defensive series as a mini-game and has made every effort halt opponents’ scoring drives by limiting their third down conversions. Getting off the field after third downs has been the focus of the Eli defense in practice and its progress has certainly shown itself in game situations.

Though much has changed since week one, the Bulldogs’ first outing of the season had to be difficult to watch for any defensive coordinator. The young defense had no answer for lightning-quick San Diego quarterback Josh Johnson, giving up 43 points and 28 first downs. Yale’s inability to stop the Toreros on third downs seemed to wear the defense out, and when the dust cleared, San Diego had almost twice as much possession time as the Bulldogs did.

But Yale’s defensive squad has grown a lot since that first game, and the improvement is obvious.

San Diego converted on an astounding 70 percent of third down situations, but since then, the Elis have held their opponents to under a 50 percent success rate, including limiting Cornell to just four conversions in 14 attempts. The newfound stinginess of the defensive line has shown immediate results for the Bulldogs, who have taken their last three after the opening day mishaps against the Toreros.

“You have to keep in mind that there are a lot young guys who are playing some important minutes for us,” defensive end Brendan Sponheimer ’07 said. “With every repetition they understand the game more, and the more you know what you are supposed to be doing on a given play, the more you can just play. A major problem with us the first week was that we were thinking too much instead of just playing the game.”

Players said that slowing teams down on offense is not entirely a matter of x’s and o’s, but has a lot to do with determination and confidence.

“Stopping third downs is largely a mental thing,” cornerback Casey Gerald ’09 said. “We have learned as a defense to understand what the opposition is trying to do and make sure they’re not able to do that.”

But as much as the Bulldogs have improved over the course of the young season, there is still much work to be done. The Dartmouth game was the first one in which the Elis recorded more first downs than their opponent. As Yale embarks on this crucial stretch of the Ivy League season, it needs to continue to improve and refine its play.

“We need to concentrate on creating more long yardage situations,” Yale head coach Jack Siedlecki said. “What you do on first and second down goes a long way toward success on third down.”

Yale’s third down goals depend greatly on the position in which its opponent begins the down. The Bulldogs hope to hold third and short conversions to under 50 percent, third and medium to less than 33 percent, and third and long to less than 15 percent for opponents, according to Siedlecki.

Yale will have to be in top shape if it plans to be succeed this weekend, when the team takes on perhaps the most mobile quarterback they have faced thus far in Lehigh’s Sedale Threatt, who leads an offense that put up 33 points and nearly toppled Harvard last weekend.