SANTA CLARA, Calif. (AP) Steelers owner Dan Rooney made his way to the visiting locker room at Heinz Field and tracked down Jim Tomsula after Sunday's game to offer a few encouraging words.

''It was obviously an honor,'' Tomsula said of the surprise greeting from the Hall of Famer. ''He just wanted to come down and tell me I was a good kid, `keep working, you're going to have good days and bad days.'''

This was one of the bad ones for Tomsula in his Pittsburgh homecoming as his San Francisco 49ers took a 43-18 beating just six days after a commanding season-opening win against Minnesota when much went right.

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Sure, there was plenty stacked against San Francisco (1-1): the short week, a cross-country flight and early kickoff time.

''If it's a lopsided game, I'm not really into talking about all the positives, to be honest with you,'' Tomsula said Monday. ''We had some drops. Nothing was glowingly beautiful yesterday. ... It's a 16-week season and we don't need to get on a rollercoaster. Keep your head focused, lock your jaw and let's get to work. Own it, fix it, move on.''

A defense that shined at stopping the Vikings - and pounding Teddy Bridgewater - was suddenly vulnerable to the deep ball and Ben Roethlisberger's strong, reliable arm, especially on third down.

Tomsula, promoted from defensive line coach to replace Jim Harbaugh, took his first loss as a head coach. He won the final game of 2010 as interim head coach after Mike Singletary's firing.

And it only gets tougher going forward with a road game at division-leading Arizona before the 49ers host Green Bay, travel to the New York Giants and then play at home against Baltimore and Seattle to round out October.

This weekend against the Cardinals, the Niners face another capable, big-play quarterback in Carson Palmer, and he will certainly look to exploit the secondary much like the Steelers did so successfully.

''They just flat out beat us. We took it in the chin,'' defensive lineman Glenn Dorsey said Monday. ''We put ourselves in a lot of bad situations uncharacteristic of our defense.''

Stopping Palmer could prove an enormous challenge given he has thrown seven touchdown passes already for 2-0 Arizona, including three of his four in Sunday's 48-23 win at Chicago to Larry Fitzgerald.

The 49ers surrendered costly plays on third down all day and didn't generate the pressure on the quarterback that worked so well in the Monday night win against Minnesota. Pittsburgh gained 14 first downs on passes.

''They came on third-and-10, third-and-5, third-and-7, third-and-2, third-and-3 and third-and-6,'' Tomsula rattled off. ''It was third-and-mediums where our biggest struggle yesterday was.''

On the offensive side, quarterback Colin Kaepernick was sacked five times after taking 52 sacks last season, second-most in the NFL. He did connect with new wideout Torrey Smith on six passes with a 75-yard touchdown in the fourth quarter while finishing 33 of 46 for 335 yards and two touchdowns with a 106.7 passer rating.

For these two to find their rhythm was a bright spot in a dismal day that had the 49ers outgained 280-106 yards in the first half before production improved after halftime.

''They definitely whipped up on us. There's no way around it,'' Smith said. ''We didn't do enough. We weren't ready. It's on us to get ready to move on. We have 14 more games left. If this were late in the year, when we really need it, there'd be room to panic.''

Notes: RB Carlos Hyde has a leg contusion that isn't considered serious. He was hit in the head during the game but passed the NFL's concussion protocol, Tomsula said. ''He was cleared, I just didn't want to put him back in,'' the coach said. ...TE Vance McDonald has a leg contusion below the knee and X-rays were negative for a fracture. Smith also had a bruised leg, noting, ''I'm walking I'm all right, I'm alive.'' ... RB Reggie Bush (calf) and WR Bruce Ellington (ankle) were still working through rehab for their injuries.

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