MIAMI — MLB officials don't know exactly what has led to the dramatic spike in home runs this season, commissioner Rob Manfred said Tuesday, but they are confident in eliminating two popular possibilities:Juiced baseballs and juicing players.Manfred said testing by two independent groups has shown — with "absolute certainty" — the baseballs fall within the standard manufacturing specifications.And he said they are confident their "state-of-the-art" drug testing program would expose any cheating which, based on the homer totals throughout the game, would have to be widespread."I know those two things for an absolute fact," he said before Tuesday's All-Star Game. "Beyond that we are in the process of trying to come to a conclusion as to what may be going on. We think there may be are a number of factors in play here."Among those, Manfred suggested are the increased dependence on home runs to score runs, a broader acceptance of strikeouts by hitters and a dropoff in the quality of pitching with teams shuttling in more relievers.He also said MLB will look into whether bats are being made differently and if the seams on the balls, as some pitchers claim, are different."Will we ever know the whole answer? Probably not," he said. "Most important is to figure out as much as we can about what's going on and maybe even more important think what it means to our fans and whether we need to do something to manage the change that is kind of taking place organically." Rays on the red carpet The route to Marlins Park for Tuesday's game including riding in the All-Star parade, which was a hot but good time for Rays DH Corey Dickerson and RHP Chris Archer , and their families. "There were a lot of Tampa Bay fans out there, that was really cool," Dickerson said. Quote of the day "He would have punctured our roof."Rays manager Kevin Cash , on Aaron Judge 's HR Derby blast off the Marlins Park roof Sunshine boys The first All-Star Game held in Florida likely will be the last until when — or if — the Rays open a new ballpark, since they won't be getting on at the Trop. Though Miami and Marlins Park posed some logistical and traffic issues, the players and coaches who hail from the Sunshine State, such as AL starter Chris Sale (Lakeland), loved the convenience factor. "To be able to be here not too far from where I live now is nice," Sale said. "I can have my family, extended family come down and experience this with me. At the end of the day this is something I'll never forget. This is something I'll be hopefully sitting in a rocking chair when I'm 80 years old telling my grandkids and great-grandkids and things like that." Miscellany • Playing off Miami's Latin American theme, first pitches were thrown by Hall of Famers (or reps of): Roberto Alomar , Rod Carew, Orlando Cepeda, Roberto Clemente, Juan Marichal, Pedro Martinez, Tony Perez and new inductee Pudge Rodriguez . Luis Aparicio was mentioned.• Bucs QB Jameis Winston was among many celebs on the field pregame, talking with NL manager J oe Maddon , C Buster Posey (of FSU) and others.• After 14 years of having the All-Star Game determined homefield advantage, Tuesday's game was back to being purely an exhibition.• The NL went into play Tuesday leading 43-42-2, and with a 360-359 edge in runs. The AL had won the last four games.• Dickerson was among 28 first-time All-Stars.