Crunching some pregame numbers

* The O's are opening their 58th home season today and are 37-20 all-time in the home opener. They are 4-0 when that first home game comes against the Tigers with the most recent win, by a 6-2 score on April 9, 2007. The Birds have won eight of their last 10 home-opening games. * The O's rank 11th in the AL with a team batting average of .222, first in ERA at 1.00 and tied for second with a team fielding percentage of .991. They lead the AL in starters ERA at 0.45. * Brian Roberts is the only Oriole to hit safely in each game so far and is batting .308 with a homer and five RBIs. He hit .359 in 39 spring at-bats. * Today's O's starting pitcher, Jake Arrieta, has made just one career start against the Tigers. He allowed just one run on seven hits over 6 1/3 innings on July 6 of last year at Detroit. Arrieta was 2-0 with an ERA of 2.60 in his final three starts of last year and went 1-1 with a 2.13 ERA over his last four home starts of 2010. * Detroit's Magglio Ordonez is a career .341 batter with six homers and 22 RBI in 42 games at Oriole Park. That is the fifth best batting average here among active players. * Today's Tigers' starter, Rick Porcello is 1-1 with an ERA of 3.00 in two career starts against the O's. He was a first-round pick, the 27th overall, in 2007. O's against Porcello: Andino: 3-for-4 Fox: 2-for-6 Guerrero: 1-for-5 Jones: 2-for-3 Lee: 0-for-1 Markakis: 2-for-6 with a HR Reynolds: 2-for-2 with a HR Roberts: 0-for-3 Scott: 0-for-1 Wieters: 0-for-4