DETROIT — Honda wants to silence its critics when it rolls out the new Accord this week.

The automaker, chastened for cheapening the Civic compact earlier this year, says that won’t happen with the midsize Accord.

It better not. The sedan is up against the toughest competition it’s ever seen.

It faces a new Nissan Altima that leads midsize sedans in highway fuel economy at 38 miles per gallon, and a revamped Toyota Camry that has cemented its place as the best-selling car in America. The stylish Hyundai Sonata, the redesigned and lower-priced Volkswagen Passat, and a new, more efficient Chevrolet Malibu also are on sale. And then there’s the European-looking Ford Fusion due out in the fall.

“It’s certainly a battle royal in the midsize sedan segment,” says Sage Marie, a Honda public relations executive who is coordinating the Accord’s marketing launch. “And we have a lot of confidence.”

Just five years ago, leading the midsize segment wasn’t that difficult. It was pretty much a two-car contest between Accord and Camry, with the Altima a distant third. Camry and Accord still lead, but in the past few years, other car companies have upped their games. American, South Korean and German rivals are chipping away at their sales.

“Honda and Toyota can no longer take it for granted that this is going to be a two-horse race,” says Jesse Toprak, vice president of market intelligence for the TrueCar.com auto pricing service. “It’s a remarkable change, how competitive the segment has become.”

The new Accord has a fresh athletic look and nicer interior. Honda says it’s aiming to beat Camry in sales to individual buyers. That excludes sales to rental car companies and other fleet buyers.

The company has released only a few details about the 2013 five-seat Accord, which it will start making Monday at its factory in Marysville, Ohio. It says the Accord’s fuel economy with be competitive with the Altima. And the price will be similar to the current Accord, which starts at $21,480.

The car’s look is still conservative, and in pictures, it resembles the 2012 version. But side creases give the new version a little more style. And the front and rear look more aggressive and athletic.

The car is a little smaller on the outside and bigger on the inside, says Honda’s Marie. It is shorter — making it easier to handle and park — and more aerodynamic, giving it better gas mileage.

The Accord’s door lines were lowered and the glass area enlarged so the driver and passengers can see better, Marie says. The changes buck the industry trend of making doors taller and windows smaller.

The car also will get all-new engines and transmissions, including a four-cylinder engine with direct fuel injection, a technology that uses less gas by mixing it with air in the cylinder. The new Accord also has a continuously variable transmission that doesn’t shift gears. That allows the engine to work at the optimal level regardless of speed.

Honda also went against trends by giving buyers the option of a V-6 engine. Hyundai, Ford and Chevrolet offer only four-cylinders in their new midsize cars.