Picked-up pieces from first-half review

After re-watching the first half of the Patriots' Week 15 loss to the 49ers, passing along some picked-up notes and observations.

1. On the Patriots' opening drive, running back Stevan Ridley was taken down for a loss on a 3rd & 1 play to force their initial punt of the evening. Linebacker NaVorro Bowman sniffed out the play and made the big hit in the backfield, but an assist should be given to defensive tackle Ray McDonald, who was outstanding throughout the game. McDonald walked right over right guard Dan Connolly on the play, driving him into the ground and freeing up a lane for Bowman to run right through. Connolly has to find a way to either seal McDonald off, drive him backwards himself, or cut McDonald to prevent him from disrupting the play.

2. The 49ers tried to run a screen pass for the shifty LaMichael James on their own opening drive, but the pass was broken up by linebacker Dont'a Hightower, who may have had his best game as a pro. From the snap, Hightower, who was aligned on the end of the line, saw the high helmet of right guard Alex Boone and the deep retreat in his stance by right tackle Anthony Davis, both tip-offs that a screen was forthcoming. Hightower wasted no time closing on the ball, and prevented the dangerous James from getting a chance to make the play. If Hightower hadn't made the play, nose tackle Vince Wilfork may have, as he too read the screen early, moved laterally to work toward the throw and be in on the action.

3. Breaking down the touchdown throw to Randy Moss, which accounted for 25 yards: The Patriots brought pressure with one additional rusher, and looked to have man coverage in the secondary with a single deep safety, Devin McCourty. Rookie Alfonzo Dennard was responsible for Moss, who faked an out-breaking route just two or three yards down the field before continuing vertically. At the point of his fake, Moss forced Dennard to stand upright and put him out of position to transition in his hips and turn and run down the field. Tight end Delanie Walker, aligned just inside of Moss, mirrored his downfield route, which made the path of McCourty to the point where the football was thrown a congested one. Once the rangy Moss got a step on Dennard, the play was all but over.

4. Depending on how one chooses to examine the game, the Patriots line either did a sufficient or very good job against Aldon Smith, as he was kept off the sack-board, but did manage two quarterback hits and an interception. One pressure concept that the 49ers like to run, which freed up Smith for one of his two quarterback hits on Sunday night, is what's called an end-tackle "game" or stunt. The rush essentially involves one player (the end or tackle) taking on the rush lane of the other, while the other player loops around. The game forces two offensive linemen to successfully complete an exchange of assignments, which can be tricky in the heat of the moment. On this play, which ended the Patriots' second offensive drive, defensive tackle Justin Smith, aligned nearly head up on guard Logan Mankins, angled outwards and split Mankins and Nate Solder, almost grabbing the two of them to prevent the exchange. Aldon Smith played off of Justin's movement, looping around and into a free rush lane to hit Brady and force the under throw.

5. Tough to put a finger on the member of the punt return team who was in theory responsible to account for a fake that involved an outside run. Running back Brandon Bolden was the exterior rusher to the side that 49ers safety Dashon Goldson took the direct handoff and ran toward for the first down, and he was cut down by the 49ers wing player on the rush. Additionally, the 49ers had their left gunner (to the side of the fake) press down the line at the snap, which, in effect, set the edge for Goldson to run around. Kyle Arrington and Marquice Cole were the hold-up players who were a hair late to diagnose the fake. That was a well-timed and better executed gamble by the 49ers.

6. The Patriots finished with an average of four yards per carry on Sunday night, though only Danny Woodhead was able to get much going on the ground. The Patriots opening things up and spreading the 49ers defense out seemed to give Woodhead creases to run through, and they also used some trap plays that got the 49ers' big defensive linemen on the move a bit. On a 2nd & 10 with 13:35 in the second quarter, the Patriots sent tight end Aaron Hernandez in left-to-right short motion to ready for a wham block at the snap. Hernandez picked up McDonald, who was shaded over center Ryan Wendell. That allowed Wendell to step to the second level and pick up Patrick Willis, while the left side of the line accounted for the Smiths. A hole off where the guard and tackle aligned pre-snap opened up for Woodhead to squirt through and he picked up nine yards. It seemed that the Patriots were more effective when they found ways to make the 49ers defensive linemen have to diagnose runs and react -- getting them on the move -- rather than just running right at them and out-muscling them.

7. Breaking down the touchdown to Delanie Walker: the Patriots looked to be in Cover 3 defense, with cornerbacks Aqib Talib and Dennard plus McCourty each responsible for one third of the deep part of the field. At the snap, the 49ers had a balanced formation, with two receivers to either side. Only three receivers were sent out on the route, with Moss pressing vertical into Talib's territory. Talib had Moss squared up, while McCourty -- who was playing center field -- opened his hips toward Moss and shaded in that direction. On the other side of the route, both Vernon Davis and Walker were pressing vertically down the field and flooded the zone of Dennard. He had no choice on the play other than to split the two receivers and hope for the best. One would think that McCourty shaded toward Moss because of the earlier touchdown in the game, fearing he would beat them over the top again, but on this play he looked out of position. With an unbalanced route, McCourty looks like he should've worked toward the other side of the field to help Dennard. Offensively, a staple to beat Cover 3 is to send four vertical routes down the field so as to force a deep zone player to have to make a decision like Dennard had to. It only took San Francisco three receivers for the all-too-easy score.

8. The perils of sending pressure and playing man coverage against Colin Kaepernick showed up on a 3rd & 8 play that led into the two-minute warning. The Patriots sent five rushers, including Hightower, and an additional safety was in the deep part of the field for back-up coverage. That vacated the middle of the field, and sensing the pressure, Kaepernick stepped up and had his best scramble of the half, taking the football down to the 15-yard line and giving his team a fresh set of downs. Because of the pressure sent and man coverage behind it, Kaepernick had ample space to run on the play.

9. The Patriots didn't use Talib to shadow a specific receiver on Sunday night, something they did against Houston last Monday. Talib was the player responsible for guarding Moss on a fade route in the end zone to close the first half, however, and Patriots fans know how adept Moss is in those situations. Talib played good leverage on the play, preventing Moss from working inside, and did well not to contact him in the end zone. In fact, it was Moss who was flagged for the push-off, an important penalty that sent the 49ers backwards and eventually helped force a field goal attempt.

10. A couple of general thoughts from the first half: Not breaking any news here, but the 49ers left many opportunities on the field. By that some token, they were also fortunate to seemingly have all of their own fumbles fall right into their arms, and a couple of Patriots fumbles bounce their way too. ... The Patriots, this scribe would argue, did a good enough job of playing with discipline and technique against the 49ers' multiple offensive looks. The linebackers read their keys well. ... Field position was an underrated aspect of the first half, and the game on the whole. The Patriots have been so good at covering kicks and flipping the field, but it felt like San Francisco was always set up in solid position, while the Patriots were working from deep in their own territory.