Dave Roberts lays out plan on how Dodgers will use new reliever Ryan Madson

Ryan Madson turned 38 on Tuesday. In 13 seasons in the majors, he reached the postseason on six different occasions and appeared in three World Series. As the Dodgers prepared to welcome him into their clubhouse, the team intended to rely on Madson’s history rather than his present, which made him available in a waiver-wire deal from Washington.

The Dodgers acquired Madson, a right-handed reliever, from the Nationals in exchange for minor-league reliever Andrew Istler. The team will pick up the $1.17 million remaining on Madson’s salary, according to a person with knowledge of the situation. Madson was expected to arrive in Los Angeles on Friday evening and be activated when the rosters expand on Saturday.

The team intends to use Madson in high-leverage situations, manager Dave Roberts said. Madson was available because Washington has plummeted out of the playoff race. Madson played a role in that tumble. He has a 5.28 earned-run average this season, and struggled earlier this month while pitching with lumbar nerve irritation. His fastball sat at 95 mph when he returned from the disabled list earlier this week, but he has given up three home runs in his last seven appearances.

“We’re betting on the stuff, and the person,” Roberts said before Friday’s game against the Diamondbacks.

Roberts suggested the Dodgers could alter Madson’s sequencing to make him more effective in the season’s final month.

“We’ll bet on giving him the best chance to have success here,” Roberts said.

The arrival of Madson could affect the return of Ross Stripling, who threw a bullpen session to test his injured lower back. The Dodgers are debating whether Stripling would be built up as a multi-inning reliever or used in one-inning bursts. With Madson in the fold, the team may be able to delay Stripling’s return, relying on the combination of Madson, Kenta Maeda, Caleb Ferguson, Scott Alexander and Dylan Floro as the bridge to beleaguered closer Kenley Jansen.

“It definitely gives us more options, having Ryan with us,” Roberts said.

SHORT HOPS: Reliever John Axford (fractured fibula) has not been cleared to face hitters, but Roberts said the team hopes he can return this season. Axford has been playing catch at Camelback Ranch and no longer requires crutches. . . . Among the players expected to be activated for the roster expansion on Saturday are second baseman Chase Utley and outfielder Alex Verdugo. Verdugo posted on Instagram on Friday that he had arrived in Los Angeles.

andy.mccullough@latimes.com

Twitter: @McCulloughTimes