A good way to determine the relative quality of a team is to look at their runs allowed versus their runs allowed. Bill James even developed a Pythagorean Theorem for baseball, finding that a team's won less record tends to resembled the square of runs scored divided by the sum of runs scored squared and runs allowed squared. I know, math is scary. Sorry about that.
But the point here is the runs scored and allowed of Arkansas and LSU tell the tale of two different teams:
LSU - 376-215 (142-113)
Arkansas - 278-224 (133-109)
Now check the records:
LSU - 34-12 (14-7)
Arkansas - 30-12 (13-7)
There's a few weird things going on with Arkansas. First, they have scored about 100 less runs than LSU, allowed 10 more runs than LSU, yet they have nearly the same record. Their Pythagorean record is 25-17, and obviously they are dramatically outperforming that number. This is a team that is outperforming its numbers.
But even more interesting is that their Pythagorean SEC record is 12-8, which they are outperforming by one game. This means that Arkansas has played better once they got to the tougher part of their schedule, which makes little sense. They are an ordinary bubble team outside of conference, but in conference, they are a legit top tier team. Go figure.
Now, a lot of their success in conference is a bit of a mirage. The Hogs won their first 8 games in conference, against Florida, Auburn, and State. OK, Florida's good, but beating up on Auburn and State is hardly grounds to brag. Since getting to the meat of the SEC schedule, Arkansas is a far more pedestrian 5-7. They were swept by Vanderbilt, and lost a series to Georgia. On the flip side, they swept a two-game midweek series versus Arizona State.
I want to say Arkansas is mirage, but they've done just enough to make me afraid. Richard's already pointed out they will throw a lefty at us, and their best pitcher is a lefty reliever. Probably the secret to their success in outperforming Pythagoras is that Stephen Richards has eight saves. If the game is close in the seventh, it's probably too late to mount a comeback, particularly for LSU's lefty heavy lineup.
LSU is a better team. We hit for a higher average, we get on base more, we have more power. We play better defense, we steal more bases, and we have a better rotation. But you can say that about just about every series. On paper, LSU is better. With Arkansas, that doesn't seem to matter.