That's a wrap on the second preseason game for the San Francisco 49ers after they defeated the Los Angeles Chargers 41-17.Only one more preseason game to go before all eyes turn to Week 1. But before that page gets flipped, let's take a look at the six biggest takeaways from tonight.Deebo Samuel returning puntsTo my surprise, the 49ers trotted out Deebo Samuel to return punts. He's always been capable of being an effective returner. But the fact that the 49ers are using him is revealing.It shows that no other player is stepping up to stake their claim for the spot. I'm sure the 49ers don't want Samuel to handle these duties and prefer another player to handle them.Jacob Cowing throws himself a lifelineSure enough, Jacob Cowing executed a video-game-like punt return touchdown. He needed that, as his roster spot on the team was fading. He was one of six 49ers with the most to gain from this game.Now, one punt return touchdown doesn't secure him a roster spot, but it does help. He threw himself a lifeline and will need to capitalize on it in the last preseason game.Carver Willis gets the startOne thing to watch entering this preseason game was who the 49ers would start at left guard. In the opener, it was Robert Jones, while Connor Colby appears to have been axed.Rookie Carver Willis got the nod to start this game, but he didn't do anything to separate himself as a lead candidate. He'll have one more shot to do so, but time is running out for him and the 49ers to figure out this spot.Purdy-Stribling connectionKnowing that Brock Purdy was going to play in this game, everyone would get a first glimpse of what his connection with rookie De'Zhaun Stribling would look like.Sure enough, the two have a strong rapport. Purdy had said early in training camp that he trusts Stribling, and he wasn't kidding. The two will be quite the tandem in the regular season.Kaelon Black runs with ferocity All eyes were on Stribling as the rookie to focus on in the preseason opener, but this time it was rookie Kaelon Black. He missed the last game due to an abductor strain.Thankfully, he returned to practice this week and was able to suit up in tonight's game. The main takeaway from watching Black is that he runs with ferocity. He may not be that fast, but he's tough. It was like watching a stack of bricks with legs running. He doesn't shy from contact and falls forward. Black can be a great change of pace from Christian McCaffrey.Sincere McCormick makes a statementAnother running back who looked solid was Sincere McCormick. He made a statement with his six-carry performance, tallying 53 yards and a score.His highlight was when he ripped off a sweet 37-yard gain, which does skew his stats. However, it was clear while watching him that he runs hard and fits well in the 49ers' offense. This is bad news for Jordan James.Austen Pleasants at left guard?After Willis got a chunk of playing time at left guard, the 49ers tried offensive tackle Austen Pleasants at left guard. This is proof that the 49ers are in panic mode.They are so desperate for options that they're trying out a tackle at guard. That tells you all you need to know. Pleasants also got hurt later in the game, so his status is up in the air moving forward.Follow Jose on X (Twitter) @JS3sanchezz and his YouTube channel to interact with him on the 49ers and more.Add us as a preferred source on GoogleFollow