Homeground Advantage in the ABL

After quite a bit of discussion lately about the variations between ballparks in the ABL, I thought it would be interesting to look at homeground advantages. I've previously asserted that teams with batter friendly ballparks, such as Melbourne and Adelaide, know how to take advantage of their own field. Based on all ABL games to date I determined the winning percentages of teams at home and on the road:

Team	Home Record	Away Record	Difference (Home – Away)
Adelaide Bite	0.667	0.375	0.292
Brisbane Bandits	0.500	0.481	0.019
Canberra Cavalry	0.542	0.158	0.384
Melbourne Aces	0.500	0.346	0.154
Sydney Blue Sox	0.500	0.481	0.019
Perth Heat	0.522	0.800	-0.278

All teams, with the exception of Perth, seem to have a homeground advantage (e.g. have a better record at home than away) - but to greatly varying degrees. The discrepancy regarding Perth is likely due to their current domination of the competition, winning the title last year and starting this year with a currently unbroken eleven game winning streak.

In a previous blog looking at batting park factors, I objectively established that the ballparks in Melbourne, Adelaide, and Canberra favoured batters. Conversely, in Brisbane, Sydney, and Perth the pitchers are much more dominant. Interestingly, these two groups of teams reoccur when looking at homeground advantages:

Team	Percentage Improvement at Home	BPF
Canberra Cavalry	243%	114
Adelaide Bite	78%	116
Melbourne Aces	44%	156
Brisbane Bandits	4%	63
Sydney Blue Sox	4%	96
Perth Heat	-35%	69

While multiple factors may account for what level of homeground advantage a team experiences, the effect displayed above is simply too distinct to ignore. It appears that teams with batter friendly ballparks have a significant homeground advantage, while teams with pitcher friendly ballparks seem to have a negligible homeground advantage.

Hence, my hypothesis that teams in smaller ballparks learn how to exploit the advantages (as discussed in my last blog on Simon Morriss) appears to hold true.

Struggling Start - Can Morriss Rebound?

Following a strong home series against the Blue Sox, the Bandits fortunes reversed this weekend in Melbourne - going 1-3 for the weekend. While still in second place, thanks to the Perth Heat killing everyone in sight, it brings there overall record to a level 6-6. Simon Morriss was pinned with two of the recent losses, and four overall, putting him in the unenviable position of having two thirds of the teams losses against his name. I've noticed Simon has been copping heat in reaction to this, and thought I would take a closer look - and see if Mr Morriss can turn his season around.

First, let's have a look at his appearances so far this year:

Opp.	Role	IP	H	R	ER	BB	SO
@Canberra	Starter	5.0	5	6	6	4	4
Sydney	Starter	4.0	7	4	2	2	4
@Melbourne	Closer	0.2	4	3	3	0	1
@Melbourne	Starter	4.0	7	5	5	0	5

Yep, rough start. After a closer look of the numbers, a few things stand out. Firstly, he's given up the most home runs of any Bandit (4). This equates to 2.63 home runs per 9 innings pitched, up from 1.58 last year. Secondly, he's leaking both hits and walks. This season, his WHIP (walks + hits per innings pitched) is up to 2.12 from 1.38 (as well as two hit batters). And finally - on a different note - his strikeout-to-walk ratio has improved from 1.61 to 2.33. So what to make of all this?

Those home runs hurt. In fact, extra-base hits hurt. The runs given up against Canberra came from two home runs and a double. Two against Sydney were from a double. He gave up a solo homer to blow the save against Melbourne, and added a pair of doubles to it in his next appearance. He's getting hit and getting hit hard - and it seems his style of pitching is poorly suited for the batter friendly stadiums highlighted in my last blog post.

One important factor is his Groundout to Flyout (or airout)  ratio (GO/AO). In a tiny ballpark like Melbourne, if you allow the batters to hit flyballs consistantly - eventually some of them are gonna clear the fence, or at least go for  extra base hits. When Chambers got blasted from the third game against Melbourne (after just two innings), he didn't induce a single groundout. Melbourne know how to take advantage of their ballparks dimensions (and so do Canberra, to a certain degree). So Morriss is getting hit, and getting hit in the wrong way. So are the other pitchers, but for Simon it is more pronounced.

Pitcher	Home GO/AO	Away GO/AO
Morriss	3.00	0.67
Maestri	7.00	2.86
Yanagawa	0.40	1.00
Chambers	3.33	0.29

Three of the starting pitchers have a very high proportion of groundouts at home, so far. For Yanagawa, the flyballs being him off him at home haven't mattered due to it's pitcher friendly nature (there is nothing at all wrong with a flyball pitcher - it only becomes a problem when the fences come a lot closer). The other numbers speak for themselves - those who can control the flyballs when away fair best - ala Maestri.

Morriss has a similar problem last year, at home his ERA was 2.65 - yet, overall it was 5.63. Whether he can adjust his approach on the road - with the ultimate aim to prevent home batters playing to the advantages the stadiums provide - remains to be seen. Simon is by no means a bad pitcher - he is a true battler and a local boy to boot - but he (like many pitchers in the league) needs to find a solution to the ballpark problem.