You don’t mess with an icon.

That much was obvious to the owners of Boston’s on the Beach, even as their landmark Delray Beach restaurant off revitalized Atlantic Avenue lagged behind the downtown’s rebirth.

The challenge was how to retain Boston’s sports bar and music venue appeal but also capitalize on its beachfront location when they broke ground on a two-month, $5 million renovation last year.

On a recent lazy Tuesday, the full outside patio at Boston’s, the buzzing bar at the new upstairs restaurant 50 Ocean and the lively bustle under the tiki hut at the new next-door Sandbar are proof that the owners didn’t stray too far from the formula.

“We knew it was time for a bigger change and before we knew it, we were in a full-scale renovation,” said Michael Walsh, president of Ocean Properties, which owns this essentially new restaurant complex next door to its Marriott on the beach.

The dive-bar feel of Boston’s has been replaced with a blend of music-and-sports bar appeal that does not suffer from schizophrenia. Wrapping around the restaurant is a wide, pooch-friendly patio with fans and cool misters for a steamy afternoon (and even a menu for Man’s Best Friend).

Inside, a wood island bar is the focal point of a room adorned as much with flat-screen televisions as with many of the classic Boston photographs that gave the old place its charm. Still there is the signed Mike Eruzione jersey (he spoke at the re-dedication last fall), the picture of Bobby Orr, Ted Williams and Larry Bird, and a host of Boston memorabilia — down to different sports photos blown up to cover each table top — that gave northerners a second sports home.

Now, out back, is a fully redesigned stage where music acts play live every day of the week (except Wednesdays and Thursdays during the offseason) with a state-of-the-art sound system. Boston’s is open until 2 a.m. for the music-lovers and night owls. It is also careful not to schedule bands during big sporting events, a precarious balancing act.

Even the Boston’s sign that hung over the small attached motel out back has been salvaged and placed over the stage. The owners didn’t want to lose the heart of a restaurant that was founded by Worcester, Mass. natives and has been here for more than 30 years.

“It had sentimental value to us,” said Walsh, who grew up in Maine, but has lived in Palm Beach County since 1974, including hanging out at Boston’s while the Marriott was built across the street.

But now, this corner at South Ocean Boulevard and Atlantic Avenue has more appeal with its two other restaurants.

What used to be the beer-soaked Upper Deck is now the upscale 50 Ocean, a refined happy hour and dinner spot that seats up to 175 people. It has floor-to-ceiling windows to take advantage of the ocean view, a bar with an aquarium built into the bar top, a quiet seating area opposite the oceanfront tables and an open-air patio shaded from the sun on the west side.

“When people come up the elevator to 50 Ocean, their mouths just drop,” said Mark DeAtley, general manager for Boston’s and 50 Ocean.

The patio overlooks the 21-and-over Sandbar, a party-all-day tiki bar for beach-goers, with sand for floors, waitresses in bikinis, and facades of a castaway island that would earn a slow clap from Disney designers. It’s a far cry from the L-shaped, old-Florida beachfront motel it replaced.

“That was the whole idea of this project, that there’s a place for everybody,” DeAtley said. “We have a diverse clientele that we deal with and they’ve all found their niche.”