The first preseason game of 2026 is in the books for the San Francisco 49ers. It ends in a 19-13 defeat to the Tennessee Titans, which is irrelevant.What is relevant is how the 49ers looked, especially in the first half. There was a ton to like about it, mostly. With that said, here are the six biggest takeaways from the 49ers preseason opener.The Flyin’ Hawaiian August 13, 2026; Santa Clara, California, USA; San Francisco 49ers wide receiver De'zhaun Stribling (15) catches the football against Tennessee Titans cornerback Cor'dale Flott (18) during the second quarter at Levi's Stadium. Mandatory Credit: Kyle Terada-Imagn Images | IMAGN IMAGES via Reuters ConnectDe’Zhaun Stribling had himself a game. It seems Kyle Shanahan made it a point to showcase Stribling’s talents since Stribling was a polarizing draft pick at No. 33.If tonight’s game is any indication, the 49ers have themselves a solid receiver. Stribling made tough catch after tough catch. Everything was strong, and he ran tough. He finished the game with seven catches for 63 yards.There was a ton to be excited about with Stribling’s performance. This has only increased the hype for what he’ll look like in the regular season. Left guard red alertAug 6, 2026; Santa Clara, CA, USA; San Francisco 49ers offensive tackle Robert Jones (65) during training camp at SAP Performance Facility. Mandatory Credit: Sergio Estrada-Imagn Images | IMAGN IMAGES via Reuters ConnectIt’s time to hit the panic button on the starting left guard position. The 49ers don’t have a starting-caliber player there. It’s not Connor Colby, who spent the entire first half at right guard.And it’s not Robert Jones, who started receiving first-team reps in camp the last week. The 49ers have a huge problem at the position, and it’s going to be their biggest liability on offense. Jaden Dugger fires quick August 13, 2026; Santa Clara, California, USA; San Francisco 49ers defensive tackle Gracen Halton (93) celebrates with linebacker Jaden Dugger (53) after a defensive stop during the second quarter against the Tennessee Titans at Levi's Stadium. Mandatory Credit: Kyle Terada-Imagn Images | IMAGN IMAGES via Reuters ConnectIf there’s one thing the 49ers love from their linebackers, it’s quickness. Jaden Dugger demonstrated that in this game, especially early on. He had one sweet run stuffed against Tyjae Spears. Dugger had great quickness and play recognition. There was zero hesitation from him. It’s clear what enticed the 49ers to draft him.Gracen Halton: the wrecking ballAugust 13, 2026; Santa Clara, California, USA; San Francisco 49ers defensive tackle Gracen Halton (93) tackles Tennessee Titans running back Tyjae Spears (2) during the second quarter at Levi's Stadium. Mandatory Credit: Kyle Terada-Imagn Images | IMAGN IMAGES via Reuters ConnectIt felt like half the time the 49ers’ defense was out there, Gracen Halton was popping off the screen. The rookie looked like a wrecking ball going against the Titans’ offensive line.The most impressive thing was how quickly he looked moving laterally. That’s going to give him a huge edge against numerous guards this year, especially when rushing alongside Osa Odighizuwa. Kurtis Rourke is sharp Aug 13, 2026; Santa Clara, California, USA; San Francisco 49ers quarterback Kurtis Rourke (14) throws a pass to San Francisco 49ers wide receiver De'zhaun Stribling (15) during a game against the Tennessee Titans in the first quarter at Levi's Stadium. Mandatory Credit: David Gonzales-Imagn Images | IMAGN IMAGES via Reuters ConnectI wasn’t sure what to expect from Kurtis Rourke in this game, but it definitely wasn’t completing 12-of-14 passes for 101 yards. He was sharp in the quarter and a half he played.Rourke probably would’ve gone the entire first half had he not injured his ribs. Hopefully he’s okay, and the 49ers kept him out as a precaution. He now becomes a player to watch in the second preseason game.Nick Martin's on the outside looking inAug 13, 2026; Santa Clara, California, USA; Tennessee Titans running back Tyjae Spears (2) rushes the ball while pursued by San Francisco 49ers linebacker Nick Martin (45), safety Ashtyn Davis (29), and safety Marques Sigle (36) in the first quarter at Levi's Stadium. Mandatory Credit: David Gonzales-Imagn Images | IMAGN IMAGES via Reuters ConnectI’ve been pointing out that Nick Martin will be a trade candidate for the 49ers after training camp, and after this game, I’m even more sure of it. He’s been leapfrogged by Dugger, a rookie.That’s indicative of his standing on the team. He didn't play well either. I’d expect him to be traded to the Titans since Robert Saleh is the one who wanted him last year. Plus, he just got a close look at him, so it makes sense to make a deal happen. 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