With some of their best hitters slumping, the Baltimore Orioles desperately need someone to pick up the slack.
Enter rookie catcher Caleb Joseph.
With homers in four straight games, Joseph will try to continue his unlikely power surge Friday night when the Orioles open a three-game set against the visiting St. Louis Cardinals.
With All-Star catcher Matt Wieters lost for the season, Baltimore has leaned heavily on Joseph and the 28-year-old has responded both offensively and defensively. Besides throwing out 17 of 35 runners attempting to steal, Joseph has heated up at the plate after a slow start.
He provided all of the Orioles' offense in Thursday's 2-1 victory at Toronto, connecting for his seventh home run in the fourth inning.
Joseph is 6 for 14 with seven RBIs in his last four games, homering in each to tie the franchise record for catchers shared by Ramon Hernandez (2006) and Gus Triandos (1959).
''We knew we had to come in and try to take care of business,'' said Joseph, batting .342 (13 for 38) in his past 11 games. ''Taking two of three is gratifying because they're coming after us hard.''
His offense has been a necessity with Adam Jones hitting .107 (3 for 28) in August and Nelson Cruz going 9 for 80 (.113) with one home run and three RBIs in his last 22 games.
Although the Orioles (65-49) have averaged only 3.1 runs over the past eight games, their pitchers have offset that with a 2.40 ERA.
Baltimore is a major league-best 22-10 since July 1, posting a 2.91 ERA. Only San Diego and Seattle's pitchers have been better in that stretch.
Thursday's victory extended the Orioles' AL East lead to five games and was their sixth straight series win. They haven't lost two in a row since June 28-29.
They'll try to win a seventh consecutive series opener when they send Chris Tillman (8-5, 3.78 ERA) to the hill.
The right-hander notched his first win in over a month Sunday, pitching seven innings of four-hit ball in a 1-0 victory over Seattle. He struck out six, walked none and improved to 3-2 with a 2.45 ERA in his past 10 starts.
Tillman has never won an interleague game, going 0-1 with a 6.35 ERA in 10 career starts.
St. Louis (61-52) comes to Baltimore after completing a 4-2 homestand with a 5-2 victory over Boston on Thursday. Kolten Wong went deep twice for his first career multi-homer game and Adam Wainwright won his 14th game to tie for the major league lead.
''He's got really impressive bat speed, always has,'' manager Mike Matheny said of Wong. ''You don't have to cheat. You just take the head of the bat to the ball and watch it jump.''
The Cardinals, who remained one game behind NL Central-leading Milwaukee, have split 18 contests since July 13 despite scoring a major league-worst 60 runs.
Justin Masterson will face a very familiar opponent in his second start for the Cardinals. He wasn't terribly sharp in his debut Saturday against Milwaukee, allowing five runs and seven hits over six innings in a 9-7 victory.
Control problems continue to plague the right-hander, who walked at least three for the sixth consecutive start. He's totaled 20 walks over 24 innings and compiled a 9.00 ERA in those outings.
Masterson is 0-2 with an 8.31 ERA in his last three starts against Baltimore after going 4-0 with a 2.30 ERA in the previous four - all with Cleveland.
The Cardinals have won the last four meetings with the Orioles, sweeping a three-game set at Camden Yards in June 2011.