If Christian Ponder's preseason is done, at least he saved his best work for his closing act.

Ponder went 7-of-9 for 48 yards on his final drive during the Minnesota Vikings' 34-14 loss to the San Francisco 49ers on Sunday night, directing a 12-play, 78-yard drive that ended with a 3-yard touchdown pass to Joe Webb on a fade route. It was as assertive and accurate as Ponder has looked all preseason, and though most of his completions were underneath the 49ers' coverage, he converted two third downs (one on a 7-yard scramble, the other on his touchdown to Webb), and the scoring pass was Ponder's second of the night. It helped him finish with his best stat line of the preseason -- 17-of-23 for 116 yards, two touchdowns and an interception -- but it also dressed things up after another ragged start for Ponder.

On the Vikings' first play, he threw too far out in front of Greg Jennings, who was in single coverage against a safety, on a deep ball off play action. He threw incomplete to John Carlson on second down, and fumbled on third down after Ahmad Brooks beat Phil Loadholt and sacked Ponder. It took the Vikings four series to get a first down, and on their first sustained drive of the night, Ponder floated a couple of high passes -- one caught by Jennings, the other caught by Stephen Burton out of bounds -- instead of driving the ball downfield.

He finished the night with an average of 5 yards per pass, not unlike much of the work he did last season, and while the night again came with a significant caveat -- Adrian Peterson was on the field for just two plays -- Ponder had opportunities to connect on a few big throws that he didn't hit. He'll likely sit out the Vikings' final preseason game Thursday night, which means fans will head into the regular season relying more on faith than concrete evidence that Ponder is progressing.

Here's a rundown of the rest of the night:

• It wasn't a good night for the Vikings' secondary. Chris Cook left the game with a groin injury (no small thing, considering all the trouble Cook has had staying on the field) and Josh Robinson spent much of the night dealing with the attention 49ers quarterback Colin Kaepernick paid to him. Kaepernick targeted Robinson four times on a 84-yard touchdown drive, hitting rookie Quinton Patton for a 19-yard gain in the slot against Robinson and connecting with Patton on a 5-yard touchdown after two completions to Marlon Moore against Robinson. If Cook is out for any length of time, the Vikings' big gamble in the secondary could become even riskier with Robinson and rookie Xavier Rhodes starting.

• Defensive tackle Kevin Williams left the game with a knee injury after a chop block in the second quarter and will have a MRI on Monday. Early indications are that the injury isn't serious, but defensive end Jared Allen was ticked about the low hit; interviewed on TV he called it a dirty play. Sharrif Floyd also is out for the rest of the preseason after a chop block caused him to have a minor knee operation, and Christian Ballard is still away from the team because of personal issues. The Vikings' lack of depth at defensive tackle, at the moment, looks a bit unnerving.

• The Vikings' offensive line had another uncharacteristically bad night. Loadholt offered little resistance to Brooks on Ponder's fumble, and was later flagged for holding. And left tackle Matt Kalil had a pair of unnecessary-roughness penalties, earning one after he joined a shoving match between Brandon Fusco and a 49ers player. Coach Leslie Frazier had to sit Kalil down for a play to cool him off, and after Kalil sustained a knee injury in a poor performance in the Vikings' second preseason game, tonight wasn't a good follow-up.

• On Ponder's interception, Burton stopped early on a crossing route and was a step shy of catching the pass. Burton's had a strong preseason, but Ponder's interception might have been a completion had Burton finished his route.

• Webb, the former quarterback who is competing with Burton for one of the final receiver spots, provided another reminder of why he might fit in as a pass-catcher. He did a nice job on his touchdown, going up for a jump ball and pulling down Ponder's pass in the corner of the end zone. With his size, strength and leaping ability, Webb could be a nice weapon in the red zone.

• As promised, Desmond Bishop got plenty of work, playing with the Vikings' first-team defense in the first half and remaining in the game with the No. 2 defense in the second half. He gave up a catch to Moore when Kaepernick stepped out of the pocket and drew Bishop toward the line of scrimmage, but Bishop stopped Kendall Hunter for a loss and made a nice open-field tackle of D.J. Harper in the fourth quarter. Though he's still struggling somewhat in pass coverage, Bishop can help the Vikings' run defense, and he looked more assertive Sunday than he did against Buffalo.

• Before he left with his injury, Cook made an impressive tackle of Chad Hall, coming across the field to drag down the receiver after a four-yard screen pass.

• Chad Greenway sold the 49ers on the idea that he was rushing before dropping back into coverage on his second-quarter interception of Colt McCoy. The turnover set up the Vikings' first touchdown, when Ponder hit Zach Line -- who turned a screen pass into a 61-yard touchdown in the Vikings' first preseason game -- for a 1-yard score.